2.4 spi tft lcd touch ce factory
TFT LCD module has always been one of the hot products in DIY industry and LCD is basically the necessary products during all projects, at the same time, serial port modules are also the popular ones, because it takes few IO and the usage is simple. This section of the 2.4S-inch TFT LCD serial SPI integrated features of compact, SPI interface.
The LCD drive ic is ILI9341. It"s a 240 * 320 (resolution), 2.4 inch TFT LCD screen.The LCD has a wide viewing angle, the contrast is also very suitable.
Professional Manufacturer: household appliances, industrial control, medical equipment, POS machine, instruments and meters, GPS navigation, financial equipment, consumer equipment, information appliances.
Please send the details enquiry to us, such as the item number, quantity for each item, quality request, Logo, payment terms, transport method, discharge place etc. We will make the accurate quotation to you as soon as possible.
As long as there is stock available, ChengHao Optoelectronic usually ships items in 1 to 3 working days for samples and within 7 to 15 days for customized order once receiving the confirmation of a new order. The order will not be confirmed until the payment reaches ChengHao Optoelectronic bank account. If we are temporarily out of stock, we will do our best to inform you of the estimated lead time.
ER-TFT024-3 is 240x320 dots 2.4" color tft lcd module display with ILI9341 controller and optional 4-wire resistive touch panel and capacitive touch panel,superior display quality,super wide viewing angle and easily controlled by MCU such as 8051, PIC, AVR, ARDUINO ARM and Raspberry PI.It can be used in any embedded systems,industrial device,security and hand-held equipment which requires display in high quality and colorful image.It supports 8080 8-bit,9-bit,16-bit,18-bit parallel,3-wire,4-wire serial spi interface. FPC with zif connector is easily to assemble or remove.Lanscape mode is also available.
Of course, we wouldn"t just leave you with a datasheet and a "good luck!".Here is the link for 2.4"TFT Touch Shield with Libraries, EXxamples.Schematic Diagram for Arduino Due,Mega 2560 and Uno . For 8051 microcontroller user,we prepared the detailed tutorial such as interfacing, demo code and development kit at the bottom of this page.
You may wish to have NEWHAVEN NHD-2.4-240320,our part number ER-TFT024-4 should meet this requirment that is the completely the same withNEWHAVEN NHD-2.4-240320.
ER-TFT024-4 is still not our general product ,we don"t have enough stock .You have to email ([email protected]) our sales to buy samples or orders. Besides the minimum order quantity is no less than 500pcs per order.The production lead time is 5-6 weeks.
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Thanks for bringing this to my attention. It appears that the upgrade package overwrites the FBTFT drivers, in particular, the Raspberry Pi bootloader. This seems to solve the problem:
I just tested this, and it looks like the difference is how SPI is enabled. In the RPi 2 it’s enabled in raspi-config, not commented out in the blacklist file. I just updated the post so it should work now!
Looks like the only difference is in how SPI is enabled. In the new release of Raspbian, SPI is enabled in the raspi-config menu under advanced settings. In older versions of Raspbian, it is enabled by commenting out the line in the blacklist file
dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p6 rootfstype=ext4 elevator=deadline rootwait fbtft_device.custom fbtft_device.name=waveshare32b fbtft_device.gpios=dc:22,reset:27 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=0
Hello..I tired to interface this lcd “https://www.crazypi.com/raspberry-pi-products/Raspberry-Pi-Accessories/32-TOUCH-DISPLAY-RASPBERRY-PI” to my Raspberry pi model B+.I got a DVD containing image for LCD in the package.I burned it to the SD card and plugged in the display.But my lcd is completly blank.But green inidcation led (ACT LED) in board is blinking.Why my LCD is Blank ?
If you have tried using the manufacturers image and the screen doesn’t work, it could be that the screen has a hardware malfunction. If the process above doesn’t work either, I would contact the manufacturer
Is your RED (POWER) LED on? I had the same problem. Green Led was blinking and screen was white. Then I noticed RED Led is off, indicating there’s something wrong with the power. I plugged into different port and it started
My Touchscreen is now working fine.The problem was for the ribbon cable on the back side of LCD.It was not connected properly.I just tighted the cable and it worked fine.Hope it will be useful tip.
Just got my Pi2 running Wheezy, working with the Eleduino 3.5 LCD without running the OEMs image… kinda. I didn’t want to rebuild the application environment again, so was avoiding flashing the SD.
I tried the steps in this tutorial. It’s very clear and easy to follow, thank you. But it didn’t work for me, I tried setting my device to flexfb. Only got white screen.
[ 0.000000] Kernel command line: dma.dmachans=0x7f35 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2709.boardrev=0xa21041 bcm2709.serial=0x631a4eae smsc95xx.macaddr=B8:27:EB:1A:4E:AE bcm2708_fb.fbswap=1 bcm2709.disk_led_gpio=47 bcm2709.disk_led_active_low=0 sdhci-bcm2708.emmc_clock_freq=250000000 vc_mem.mem_base=0x3dc00000 vc_mem.mem_size=0x3f000000 dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait fbtft_device.custom fbtft_device.name=flexfb fbtft_device.gpios=dc:22,reset:27 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=0
thank you for your great tutorial, it got me on the right way. unfortunataly i only see some boot messages on the lcd and then it turns black. maybe you could give me a hint on how to get it working entirely.
i have a watterott display (https://github.com/watterott/RPi-Display) and changed the device-name to “rpi-display”. i use a rsapberrypi 2 and hae the latest raspian image installed.
Did you check to see if your device is supported yet? The device name should be specific for your screen, as listed in the fbtft file linked to in the beginning of the post
I too have a raspberry pi 2, and a waveshare spotpear 3.2 RPi lcd (v3) and I just can’t get it to work! I suspect I have a faulty LCD, but thought I’ll try this forum for help before I sent it back.
Soon as the pi is powered, the LCD lights up all white, with a few vertical pixels coloured at one of the edges, and nothing else. I don’t think that should happen – not at least before the BOIS has started up.
Anyway, point 1, says to change to dev/fb1 – I don’t have fb1. Only fb0 appears to be there. is that a clue what could be wrong? I have enabled SPI (is there a command to tell if its enabled?) I have also ran spidev to troubleshot (though I haven’t a clue what I means)
Any ideas what going wrong? I am using the latest “2015-02-16-raspbian-wheezy_zip”. Enabled SPI. done all the steps. Even changed mmcblk0p2 to mmcblk0p6 as suggested by Dabomber60 (but that freezes for me)
[ 0.000000] Linux version 3.18.5-v7+ (pi@raspi2) (gcc version 4.8.3 20140106 (prerelease) (crosstool-NG linaro-1.13.1-4.8-2014.01 – Linaro GCC 2013.11) ) #1 SMP PREEMPT Fri Feb 6 23:06:57 CET 2015
It seems all appears to be working – just the LCD is still all white with a single line of coloured pixels on edge) and nothing else. Is there a way to output, like jeff G script, of touch points?
I had the same one, I finally found a driver for it here: http://www.waveshare.net/wiki/3.2inch_RPi_LCD_(B) you will need to translate the page, but unpack the driver then run sudo ./LCD-show/LCD32-show. It should reboot and all will be good with the screen :)
My system: Raspberry Pi 2 Model B with Raspian Wheezy from Febuary 2015. LCD display of Sainsmart 3.2 http://www.conrad.de/ce/de/product/1283498/Raspberry-Pi-Display-Modul-Touch-Display-81-cm-32/?ref=home&rt=home&rb=1
dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 cgroup_enable=memory elevator=deadline rootwait fbtft_device.custom fbtft_device.name=sainsmart32_spi fbtft_device.gpios=dc:24,reset:25 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=90
sainsmart32_spi width=320 height=240 buswidth=8 init=-1,0xCB,0x39,0x2C,0x00,0x34,0x02,-1,0xCF,0x00,0XC1,0X30,-1,0xE8,0x85,0x00,0x78,-1,0xEA,0x00,0x00,-1,0xED,0x64,0x03,0X12,0X81,-1,0xF7,0x20,-1,0xC0,0x23,-1,0xC1,0x10,-1,0xC5,0x3e,0x28,-1,0xC7,0x86,-1,0×36,0x28,-1,0x3A,0x55,-1,0xB1,0x00,0x18,-1,0xB6,0x08,0x82,0x27,-1,0xF2,0x00,-1,0×26,0x01,-1,0xE0,0x0F,0x31,0x2B,0x0C,0x0E,0x08,0x4E,0xF1,0x37,0x07,0x10,0x03,0x0E,0x09,0x00,-1,0XE1,0x00,0x0E,0x14,0x03,0x11,0x07,0x31,0xC1,0x48,0x08,0x0F,0x0C,0x31,0x36,0x0F,-1,0×11,-2,120,-1,0×29,-1,0x2c,-3
ads7846_device model=7846 cs=1 gpio_pendown=23 speed=2000000 keep_vref_on=1 swap_xy=1 pressure_max=255 x_plate_ohms=60 x_min=300 x_max=3800 y_min=700 y_max=3400
The LCD display shows the raspberry correctly. However, the touch screen input does not work. The mouse pointer can I move correctly with your finger, but I can not select things (function of the left mouse button).
Can someone upload SD card image that works with RBP2 ? My idea is to use Eleduino TFT as additional screen and play movies via HDMI.. is it possible?
Do not follow this article when you don’t know what kind of LCD module. In my case, I follow all of this and my raspberry pi cannot boot anymore. I will try to recover, but I think I should format my SD card and reinstall OS.
Expecting this would builtin driver module within kernel and help with avoiding mistakenly overwriting anything. But with this is cause LCD screen to go blank white and no boot activity. Also noticed on HDMI it get stuck on Initial rainbow screen and stuck on that.
Does anyone tried splash boot screen with waveshare v4 LCD and Rpi2? I tried to follow some example from https://github.com/notro/fbtft/wiki/Bootsplash but no success.
Great tutorial thanks; got an X session working great 1st time. Has anybody managed to get Kodi/XMBC working on the LCD either Kodi standalone, Raspbmc or Xbian?
fbtft_device name=waveshare32b gpios=dc:22,reset:27 speed=48000000 width=320 height=240 buswidth=8 init=-1,0xCB,0x39,0x2C,0x00,0x34,0x02,-1,0xCF,0x00,0XC1,0X30,-1,0xE8,0x85,0x00,0x78,-1,0xEA,0x00,0x00,-1,0xED,0x64,0x03,0X12,0X81,-1,0xF7,0x20,-1,0xC0,0x23,-1,0xC1,0x10,-1,0xC5,0x3e,0x28,-1,0xC7,0x86,-1,0×36,0x28,-1,0x3A,0x55,-1,0xB1,0x00,0x18,-1,0xB6,0x08,0x82,0x27,-1,0xF2,0x00,-1,0×26,0x01,-1,0xE0,0x0F,0x31,0x2B,0x0C,0x0E,0x08,0x4E,0xF1,0x37,0x07,0x10,0x03,0x0E,0x09,0x00,-1,0XE1,0x00,0x0E,0x14,0x03,0x11,0x07,0x31,0xC1,0x48,0x08,0x0F,0x0C,0x31,0x36,0x0F,-1,0×11,-2,120,-1,0×29,-1,0x2c,-3
ads7846_device model=7846 cs=1 gpio_pendown=17 speed=1000000 keep_vref_on=1 swap_xy=0 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900
After following this tut to the letter on a brand new image of Raspian, I find that the touch driver does not function. Anyone experience the same? Basically all I did was image a current copy of rasping, did a apt-get upgrade, and then did this tutorial. Then the touch driver does not work, meaning the pointer does not respond.
The reason I did this was because on a production version of my system I added the 3.2 screen and it worked great except for the x-axis. So I wanted to see if there was something in my system that was interfering or if this is another error. Now with a raw rasping the driver does not work at all. I wonder if the touch pin has changed since the kernel is using BCM pins instead of GPIO pin numbers?
I have exactly the same problem. I also installed a new version of Raspbian, and the LCD part works fine (except all the windows are way too large), but the touch part doesn’t work at all… I’m using Waveshare Spotpear 3.2″ V4.
I remember that I plugged in the screen wrongly one time, before configuring any of the GPIO pins. Can this have damaged the screen? Still it’s weird that the display part works well and the touch part not at all.
I do not think that has anything to do with it. Other than power pins, the rest are communication. If it still works then you are good. No, there is something else. I do suspect it us related to the BCM pin numbering. The real question is… Why isnt the eeveloper responding? I have since abandoned this TFT because of his lack of response.
Touch actually goes through one of the SPI pins I think. Either the driver is toast with the required kernel update or the driver is using the wrong pin. It is very likely the this works well with previous raspian versions, but not with the new B+ and with the new kernel.
I am trying to use the sainsmart 2.8″ lcd sold through microcenter, using the sainsmart32_spi … seems to have the same pinouts, should I be able to get this to work? I am stuck at the white out screen on the lcd, doesn’t seem to recognize the module either.
The SainSmart 3.2 sold by MicroCenter (20-111-971) is actually the exact same WaveShare SpotPear v3 documented here. So maybe your 2.8 would work if you tried a WaveShare driver?
Unfortunately I’ve tried that ( a few times actually) but the file still doesn’t exist. Thanks very much for the assistance anyway. I must be doing something wrong. My Raspian came from a Noobs installation, I’m wondering if I should try installing the OS from somewhere else. My LCD screen didn’t come with a CD or any docs so I’m completely in the dark here.
I have just found a way to get this file on my system! Apparently its part of the fbturbo installation. I found it here http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=45746&start=75 (under experimental enhanced x driver (rpifb).. Sorry if this is obvious to everyone but I am SUCH a noob at this!!
Ok, what am I doing wrong. I am using a fresh install of the newest raspbian, on a Pi 2. After doing the first two steps and rebooting I get the rainbow screen, then the boot up process, and then my screen just goes black with a flashing cursor in the top left. I am not able to enter any commands or anything…like the pi is halting just after boot up. Any thoughts/suggestions would be greatly appreciated. Thanks.
Well figured out that step 1 was causing my problems. I’m guessing it is shutting off my hdmi feed and trying to switch it over to the SPI, am I guessing right? If so, not sure how I’m suppose to complete the rest of the steps if my hdmi output gets turned off before the LCD is actually set up to work…that sounds kind of smartass-like, which is not my intention, just looking for some clarification on what is going on in that first step as I am fairly new to this stuff. Thanks.
Anyway, I was able to do the rest of the steps with no problem. LCD didn’t work, but I am using a Waveshare 3.5, which doesn’t look to be supported yet. Mostly I am trying to play around and see if I can get it working somehow. Anyone found a way to do this yet?
Here is a link to an updated image from waveshare. Upon install it got the display up and running, but I still do not have touch functionality. I’ve been playing around with it, but it has been to no avail…hopefully someone better at this stuff from me can get the touch working.
I am having an issue with getting the GUI back. Every time I use startx my pi just sits there for about two minutes saying “No protocol specified”, and then it just gives up. I went through this tutorial about four times now and am not certain why it is doing this. I have the exact same LCD as is in the tutotial (WaveShare 3.2b). any help would be great.
Hi I am making a project for school,using the raspberry pi b+ and waveshare spotpare 3.2b. Everything works except the touch input doesn’t work. Any help would be appreciated very much.
So complicated (and especially the line with myriad of hexadecimal values) that if you succed you’re a very Lucky person. Don’t do that except if you have time to kill.
Great write up – worked first time for me. The only difference is by modules blacklist file was empty so there was no change needed there. Maybe to do with me being on a newer rasbian?
Thanks for the tutorial. It works, but I get the boot/command line stuff on the HDMI monitor and the LCD only comes on when I do startx. Is there a way to get everything to appear on the LCD screen?
I have a Tontec 7 inch touchscreen with a Raspberry Pi 2 B. After following the instructions the touch screen is functioning but not properly… The only are that works is the upper left (and only a small area of that). I tried changing the width and height in the modules but it didnt change anything. Also the xy seems to be reversed, I changed the swap_xy to 1 but again no change on the screen.
Now the OS freezes at the emulation station loading screen, and if I connect my lcd it gives me a lot of error messages which I can only see on the 3.2 inch screen.
This was an excellent tutorial. I have gotten an output to the screen, but no touchscreen usage . I have the Waveshare SpotPear 3.2 Inch LCD V4 screen, but using Raspberry PI 2 with wheezy. Any ideas?
I filed the steps to calibrate the screen but it did not work.I think because it did not find the TFT pin, because I think the touch problem is the assigned pin to control it changed.
I actually used the driver from here http://www.waveshare.com/wiki/3.2inch_RPi_LCD_(B) , from a new wheezy build, did nothing except enable SPI in config, install driver, and change mmcblk0p2 to mmcblk0p6 in cmdline.txt and it all worked, no drama.
Hi I managed to set up my touch screen ok but I now have the issue that everything desktop fits fine but the windows I open are all huge and I can’t remember how to change the size and cannot see the option in desktop preferences any idea what I have to do and is it at all possible to install kodi to run through the raspbian is as this would be a lot my useful than having to keep swapping os on every boot up many thanks in advanced hope you can help me
Advice to all who have the drivers from the (touch)screen manufacturer and cannot obtain those otherwise: you can skip everything and go to the update steps skipping the kernel and kernel modules update (as mentioned by the author) so that you don’t override the preinstalled drivers. I have a Waveshare 3.5″ RPi v3 (not the 3.2″ supported by notro’s drivers) and actually managed without any problems to get notro’s drivers make it work. However I am still reading about the xinput and xinput-calibrator to figure out how to include it as a kernel module so that I can compile my own kernel and add it there.
i have raspberry pi 2 with 3.2 inch rpi lcd v4 waveshare spotpear.i have done as per your instructions.the display is working but touch screen not working.error shows waveshare32b module not found as well as touch screen module not found messages.
Unfortunately I have lost the Touch facility on my Waveshare 3.5″ LCD Touchscreen? Can you offer any reasons as to why? I copied the Raspbian image to my Raspberry Pi from the Waveshare website first of all. The Touchscreen displays but is not reactive with any touch
I have purchased a raspberry pi B+ total kit and waveshare 3.2 TFT display online. In the package i have been given a pre-loaded NOOBS installed SD card. I did not even start anything yet. What should i do what r the things needed and how to connect the display i really want to know. I need help as i don’t know anything. Does the above solution help or will u suggest something………………..
Hi great article thanks. I am trying to get a waveshare 7 inch LCD with capacitive touch running it works with the suppled image but if you upgrade it breaks the capacitive touch. I have a sense-hat and GPS which require the latest kernel and RASPIAN image and the install program for the screen replaces the /lib/modules directory and the kernel with older ones. I need to be able to install the touch drivers into a new clean OS can anyone give me some pointers? Thanks
I should add that the screen is plugged into the HDMI port and always works. The capacitive touch is driven from the USB port which also supplies power.
For anyone who have those unbranded cheap TFT touch modules and cannot get it to work with this guide, I had success on my 3.5″ with the following steps: http://pastebin.com/89qmFbPB
I have the WaveShare 3.5 (A) and cannot get it to work with the Kali Linux with TFT for Raspberry Pi. Have anybody gotten the A to work? (Not the B, theres instructions for the B already and dont work with A)
So I have the original image that came with my screen and it works fine with the LCD but my problem is that I want to use my LCD screen with other distros (at this time I am trying to use it with Kali Linux with TFT support by default https://www.offensive-security.com/kali-linux-vmware-arm-image-download/) What do I have to do to transfer the needed files from the original image that WORKS with the screen and use them with another image?
I originally bought this bundle http://www.amazon.com/gp/product/B013E0IJUK?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00 with an RPi LCD V3 and no extra documentation on the specifics on the chipset. I tried with the bftft drivers but since I have no idea what to call this screen I just suppose it isn’t supported.
I’ve followed your instructions and am only getting a white screen stil. I am using the Osoyoo 3.5 inch touchscreen from Amazon. http://www.amazon.com/gp/product/B013E0IJVE?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00
I’m not sure if the Jessie kernel is compatible – can anyone please confirm or not ?? Adafruit states that their setup for TFT screens are Wheezy only ; is this a different setup ??
I am using the same LCD and followed your tutorial. Have your tested the guide lately? Are you certain that it works? I see the boot messages on console but I get white screen as GUI starts.
Oct 16 17:38:48 spare kernel: [ 12.544859] graphics fb1: fb_ili9340 frame buffer, 320×240, 150 KiB video memory, 4 KiB DMA buffer memory, fps=50, spi0.0 at 48 MHz
After I rebooted in step 3, my raspberry pi won’t boot up again. It goes thru the process of booting and the text scrolls down and every thing says “ok”. Then instead of going to GUI it just guys to a black screen on my monitor with a blinking underscore in the top left corner. Anyway to get around this? or should I start over with a fresh disk image??
Please check out my answer, it may help you if it works. I’m not in that case but I’m assuming that the desktop environment simply doesn’t automatically start running anymore… This can be changed in the raspi-setup
Try typing ‘startx’ if you problem isn’t solved (assuming you’re using Raspbian and LXDE), it should start the desktop environment you’re used to see. What you’re seeing is the Command Line Input interface (CLI), the most basic way to interact with a computer. Hope I helped you a little
I have tried to set up waveshare 32b on my Pi B using the latest Raspian download. I learned a lot in the process using Windows Putty, Nano etc. I have repeated the setup process several times from scratch and included the corrections for possible overwriting. My Waveshare SpotPear 3.2 inch RPi LCD V4 just shows a white screen. Any suggestions?
I’d suggest that you use the included installation disk to make a clean install on another SD card to see if the screen itself works fine or not, then try to repeat the process of installation after upgrading
This process worked for me except for two things. The screen only shows 25* of any page so the most important buttons are inaccessible, and now the Wifi does not work and cannot be activated where it worked fine before the reboot. Any suggestions?
Hi, I am using raspberry pi 2 with raspbian jessie installed. I the waveshare spotpear 3.2 v4. The above instructions are not working. and after completing the steps there was no display from hdmi or lcd. One things to notify is.: the etc/modules files only had i2c-dev and not snd-bcm2835.
I am trying to get this to work with Retro Pie 3.3.1 and the Waveshare3.2″ v4 but I only get the terminal on the lcd and emulation station starts on hdmi. to get it working with retro pie i just replaced startx with emulationstation. how do i get this to work?
Sir, Your post has very useful to me. i am using Tinylcd. but i cant get display. i am performing all the steps in your post. i cant get touch controller information from the product website and also i am using RASPberryPi B+ model. could u please give me best solution to my work. Than you.
what if OS is not Raspbian, any other distro like Yocto project, etc.? Could you please specify process without “rpi-update” that makes driver installation process more generic, not dedicated to Raspbian.
I completed all steps except for the last one (I want it to boot to console). However, when I reboot, it never completes the boot process. I start in recovery mode and check the cmdline.txt file and it is exactly how it appears on this page. I copied the kernel info as well, but I am not sure if it correct as I cannot get to it to check. Any suggestions? I might just reinstall the OS and start over…
i installed android OS in raspberry pi 2. can i use same LCD touch screen set up for android installed raspberry pi 2 which you are used for raspbian.
Is it normal the white back light during the whole process of initializing (I suspect that during the transportation trere is a deffect)? The problem is that I missed the step #1 and I performed it at the end. Unfortunately I don’t have any monitor available right now – neither “normal”, neither LCD :))))). Is it possible turning back the system or the only option is reinstallation of the Raspbian?
I have KeDei 3.5 inch TFT version 4.0 by Osoyoo. (released after January 1 2016) how do i get it working with vanilla Raspbian Jessie (do not want to install the image sent by the seller)
I’m trying to use an original Raspberry Pi model B with a cheap 3.5 inch 320×480 LCD which allegedly was manufactured to work with the Pi and has the correct fittings to fit over the GPIO pins. The operating system is the latest, downloaded yesterday and installed with NOOBS. I can’t get past step 2 of this guidance. When I reboot after using raspi-config I can see text generated as the Pi boots, then the HDMI fed screen goes blank apart from a flashing cursor in the top left hand corner. The LCD just remains white with nothing else on it. I have missed out step 1 and rebooted after step 2 and the screen functions as I would expect. Does anyone have any ideas please?
now when it seem WaveShare release their own custom image or sources, same thing happens kernel panic. unfortunately this time around doing the same trick doesn’t save the day !
Thanks for the great tutorial. I do have a question. Once you install the drivers for the lcd are you effectively disabiling the hdmi port or is it still available to use and will the pi function with both displays. I have a pi 3
once you install the drivers it replaces the kernel by disabling hdmi output and enables it for LCD. i don’t think we have a solution to get em both working at the same time. ( you are encouraged to search for it )
Thanks for the guide, have been doing this with my son but once we leave raspi config and reboot all we get is a black screen with a flashing white horizontal line (dash). Can you help? I have looked in the comments at the end of the article but no one else appears to have this issue.
My Rpi3 gets “ERROR: could not insert ‘spi_bcm2708’: No such device” after I enable SPI in the raspi-config.My Rpi3 is freezing on the rainbow screen after I reboot at the end of step 3. I’ve tried adding boot_delay=1 to config.txt.
if any interested, now i have a raspian image working on raspberry 3 with Waveshare 3.5, also with sdr support for dongles and FreqShow working perfectly on touch
I’m a proper novice, have no coding experience. A these tutorials and walk throughs are invaluable. So thank you in advance for all the help and support.
I tried following your tutorial but I got stuck right at the first step… I enter sudo nano /usr/share/X11/xorg.conf.d/99-fbturbo.conf the whole screen is blank except for the command list at the bottom…
ads7846_device model=7846 cs=1 gpio_pendown=17 speed=1000000 keep_vref_on=1 swap_xy=0 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900
I’d like to find the driver software for my 7″ LCD with touch (official Pi unit) so that I can use it in buildroot. I wanted to make sure this kernel is the one before I started digging further.
I started through your tutorial and completed step 3 and rebooted. After the Raspberry screen and some of the boot text on my HDMI monitor, I now have a black HDMI monitor and a white screen on my LCD. Does this mean that the bootloader was overwritten or something else is wrong? How am I supposed to enter in the proposed fixes to the bootloader, when I can’t get the RPi to boot? Do I have to interrupt the boot process at some point to reinstall the bootloader or what?
Its a script. Download and instead of running sudo ./LCD4-show run cat ./LCD4-show to simply display what it does without actually running it. The commands are fairly simple modifying a few files. I actually saved the LCD-show.tar.gz on my own server for faster future download but also for backup as it saved me tons of hours (if that’s a measuring unit for time :) )
I used this link though (smaller file ~ 50 KB, fast download) http://www.waveshare.com/w/upload/4/4b/LCD-show-161112.tar.gz and replaced LCD4-show with LCD32-show in the last line.
I’m using RasPi Zero with latest (as of last week) Jessie Raspbian. Did you run the script? If it didn’t work and you have modified other files in the process of making it work, I would recommend installing a fresh installed image on a new card and running the script. Can you suspect the screen being faulty or got “burned” in the process?
i bought a 3.5 inch tft lcd screen from banggood. and i have installed raspian jessie, the latest version, in my sd card. but when i power on my Pi, only a white backlit screen comes. there are no images or graphics whatsoever.
The owner of this article should including a WARNING in the header that if someone follows the steps, they will install a deprecated driver (which is only visible as tiny text on its gethub page here https://github.com/notro/rpi-firmware). This driver after install will break Raspberry Pi and the SD card will need to be reimaged, for some less experienced users, this could also mean lost work if they failed to backup their code or resources. On windows, it requires installing Linux reader software and it takes a long time to fix this f**kup which could easily have been avoided if the author had and sense of responsibility.
Will your system work with my SainSmart 2.8″ 2.8 inch TFT LCD 240×320 Arduino DUE MEGA2560 R3 Raspberry Pi ? I would like to know before not be able to back out. Thanks, Lee
hello. I really appreciate your blog post. I have a raspberry pi 3 B. I have been unable to get my waveshare 3.2 screen to work.I am at a complete loss for what to do. I do step 2 I change fb0 to fb1 and then follow your directions I don’t get the prompt to reboot; however, I do it manually with sudo reboot. that works fine then I complete step three and that works just fine; however once I reboot from getting those drivers and when I attempt to reboot it is unsuccessful and then my whole raspberry pi will not restart. then when I power it back on it will just shut back off. I then have to redo noobs onto a new SD card I would GREATLY appreciate anyones help
I ‘m actually using a LCD Waveshare3.2” , I followed your steps to setup the lcd touchscreen for my rpi and it work but I have a problem with the resolution because if I open a repertory I do not see the whole contents on the screen .
hey Thanks for this good post …I have capacitive touchscreen which i brought from the link below..can you guide how i can configure the kernel modules…It will be very helpful for me…Thanks
hey Thanks for this good post …I have capacitive touchscreen which i brought from the link below..can you guide how i can configure the kernel modules…It will be very helpful for me…Thanks
I did a 5inch LCD for my raspberry pi. I dont use the touchscreen so i didnt have to install any drivers. It works out of the box but doesnt cover the whole screen unless you open the terminal and do:
HI I have my RPI running Pi Presents on a view sonic TD2230 Touchscreen. It all works fine, touching the click areas can navigate you thru my presentation, The problem arises when you use multitouch gestures like you would on a iPhone. Pinch or expand etc… and then all touch ability goes away. I can still control the presentation via a mouse, but I don’t get touch control back until I either relaunch Pi Presents, or if I unplug and plug the usb cable going to the touchscreen.
Could you provide me with a os image of open elec that you already built for the waveshare spotpear v4 3.2 inch touchscreen,because I cannot make sense of your website’s instructions?
Much of this is outdated on Raspbian Stretch where device tree overlays (see https://www.raspberrypi.org/documentation/configuration/device-tree.md) provide for most of the configuration automatically.
In the case of the WaveShare driver, their setup script from their “LCD_show” repository will copy a device-tree overlay to /boot/overlays/ that provides most of the module config etc via boot-time device-tree patch.
You still have to add a “dtoverlay” directive in config.txt to enable it, copy it in place, and make some cmdline changes, then configure X. so it’s not trivial. But it doesn’t need to be this in depth either.
After I did the step that “INSTALL THE FBTFT DRIVERS” and then reboot, my raspberry pi couldn’t boot successfully and the green light is always on, could you help me solve this problem? Thank you.
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You can also look at portable monitor touchscreens which run from the laptops battery and are small 1.44 inch touch screen. They can also be used for projects involving single board computers. Additionally, we also have a lot of options for smart tv touch screens which are great to incorporate into home entertainment systems and allow users to surf the net, send messages on more right from their living room.
Look through Alibaba.com listings for touch screen panels and find the perfect one for your customers. Start ordering today from our suppliers and ask them for more information if needed.
Nextion is a Human Machine Interface (HMI) solution combining an onboard processor and memory touch display with Nextion Editor software for HMI GUI project development.
The provided display driver example code is designed to work with Microchip, however it is generic enough to work with other micro-controllers. The code includes display reset sequence, initialization and example PutPixel() function.
If driving the backlight of the C version display with 12 Volts and a series resistor, substituting a D version display will not work since the four LEDs need more than 12 Volts to get the same current flowing.
This TFT display is big (2.8″ diagonal) bright and colorful! 240×320 pixels with individual RGB pixel control, this has way more resolution than a black and white 128×64 display.
As a bonus, this display has a resistive touchscreen attached to it already, so you can detect finger presses anywhere on the screen. This display has a controller built into it with RAM buffering so that almost no work is done by the microcontroller.
The display can be used in two modes: 8-bit and SPI. For 8-bit mode, you’ll need 8 digital data lines and 4 or 5 digital control lines to read and write to the display (12 lines total). SPI mode requires only 5 pins total (SPI data in, data out, clock, select, and d/c) but is slower than the 8-bit mode. In addition, 4 pins are required for the touchscreen (2 digital, 2 analogs).
This 2.8 inch SPI Touch Screen Module is wrapped up into an easy-to-use breakout board, with SPI connections on one end and 8-bit on the other. Both are 3-5V compliant with high-speed level shifters so you can use with any microcontroller. If you’re going with SPI mode, you can also take advantage of the onboard MicroSD card socket to display images.
The Serial Peripheral Interface (SPI) is a synchronous serial communication interface specification used for short-distance communication, primarily in embedded systems. The interface was developed by Motorola in the mid-1980s and has become a de facto standard. Typical applications include Secure Digital cards and liquid crystal displays.
SPI devices communicate in full duplex mode using a master–slave architecture usually with a single master (though some Atmel and Silabs devices support changing roles on the fly depending on an external (SS) pin). The master (controller) device originates the frame for reading and writing. Multiple slave-devices may be supported through selection with individual chip select (CS), sometimes called slave select (SS) lines.
Sometimes SPI is called a four-wire serial bus, contrasting with three-, two-, and one-wire serial buses. The SPI may be accurately described as a synchronous serial interface,Synchronous Serial Interface (SSI) protocol, which is also a four-wire synchronous serial communication protocol. The SSI protocol employs differential signaling and provides only a single simplex communication channel. For any given transaction SPI is one master and multi slave communication.
MOSI on a master connects to MOSI on a slave. MISO on a master connects to MISO on a slave. Slave Select has the same functionality as chip select and is used instead of an addressing concept.
The signal names above can be used to label both the master and slave device pins as well as the signal lines between them in an unambiguous way, and are the most common in modern products. Pin names are always capitalized (e.g. "Chip Select", not "chip select").
If a single slave device is used, the SS pin may be fixed to logic low if the slave permits it. Some slaves require a falling edge of the chip select signal to initiate an action. An example is the Maxim MAX1242 ADC, which starts conversion on a high→low transition. With multiple slave devices, an independent SS signal is required from the master for each slave device.
Most slave devices have tri-state outputs so their MISO signal becomes high impedance (electrically disconnected) when the device is not selected. Devices without tri-state outputs cannot share SPI bus segments with other devices without using an external tri-state buffer.
To begin communication, the bus master configures the clock, using a frequency supported by the slave device, typically up to a few MHz. The master then selects the slave device with a logic level 0 on the select line. If a waiting period is required, such as for an analog-to-digital conversion, the master must wait for at least that period of time before issuing clock cycles.
During each SPI clock cycle, a full-duplex data transmission occurs. The master sends a bit on the MOSI line and the slave reads it, while the slave sends a bit on the MISO line and the master reads it. This sequence is maintained even when only one-directional data transfer is intended.
Transmissions normally involve two shift registers of some given word-size, such as eight bits, one in the master and one in the slave; they are connected in a virtual ring topology. Data is usually shifted out with the most significant bit first. On the clock edge, both master and slave shift out a bit and output it on the transmission line to the counterpart. On the next clock edge, at each receiver the bit is sampled from the transmission line and set as a new least-significant bit of the shift register. After the register bits have been shifted out and in, the master and slave have exchanged register values. If more data needs to be exchanged, the shift registers are reloaded and the process repeats. Transmission may continue for any number of clock cycles. When complete, the master stops toggling the clock signal, and typically deselects the slave.
Transmissions often consist of eight-bit words. However, other word-sizes are also common, for example, sixteen-bit words for touch-screen controllers or audio codecs, such as the TSC2101 by Texas Instruments, or twelve-bit words for many digital-to-analog or analog-to-digital converters. Multiple SPI devices may also be daisy-chained to conserve pins.
Every slave on the bus that has not been activated using its chip select line must disregard the input clock and MOSI signals and should not drive MISO (i.e., must have a tristate output) although some devices need external tristate buffers to implement this.
In addition to setting the clock frequency, the master must also configure the clock polarity and phase with respect to the data. Motorola SPI Block Guideclock polarity and phase) respectively, a convention most vendors have also adopted.
For CPHA=0, the "out" side changes the data on the trailing edge of the preceding clock cycle, while the "in" side captures the data on (or shortly after) the leading edge of the clock cycle. The out side holds the data valid until the trailing edge of the current clock cycle. For the first cycle, the first bit must be on the MOSI line before the leading clock edge. An alternative way of considering it is to say that a CPHA=0 cycle consists of a half cycle with the clock idle, followed by a half cycle with the clock asserted.
The MOSI and MISO signals are usually stable (at their reception points) for the half cycle until the next clock transition. SPI master and slave devices may well sample data at different points in that half cycle.
Note that in Full Duplex operation, the Master device could transmit and receive with different modes. For instance, it could transmit in Mode 0 and be receiving in Mode 1 at the same time.
In the independent slave configuration, there is an independent chip select line for each slave. This is the way SPI is normally used. The master asserts only one chip select at a time.
Pull-up resistors between power source and chip select lines are recommended for systems where the master"s chip select pins may default to an undefined state.pull-up resistors prevent other uninitialized slaves from responding.
Since the MISO pins of the slaves are connected together, they are required to be tri-state pins (high, low or high-impedance), where the high-impedance output must be applied when the slave is not selected. Slave devices not supporting tri-state may be used in independent slave configuration by adding a tri-state buffer chip controlled by the chip select signal.
Some products that implement SPI may be connected in a daisy chain configuration, the first slave output being connected to the second slave input, etc. The SPI port of each slave is designed to send out during the second group of clock pulses an exact copy of the data it received during the first group of clock pulses. The whole chain acts as a communication shift register; daisy chaining is often done with shift registers to provide a bank of inputs or outputs through SPI. Each slave copies input to output in the next clock cycle until active low SS line goes high. Such a feature only requires a single SS line from the master, rather than a separate SS line for each slave.
In electrically noisy environments, the SPI standard has few signals, and it can be economical to reduce the effects of common mode noise by adapting SPI to use low-voltage differential signaling.
Some slave devices are designed to ignore any SPI communications in which the number of clock pulses is greater than specified. Others do not care, ignoring extra inputs and continuing to shift the same output bit. It is common for different devices to use SPI communications with different lengths, as, for example, when SPI is used to access the scan chain of a digital IC by issuing a command word of one size (perhaps 32 bits) and then getting a response of a different size (perhaps 153 bits, one for each pin in that scan chain).
SPI devices sometimes use another signal line to send an interrupt signal to a host CPU. Examples include pen-down interrupts from touchscreen sensors, thermal limit alerts from temperature sensors, alarms issued by real time clock chips, SDIO,
SPI lends itself to a "bus driver" software design. Software for attached devices is written to call a "bus driver" that handles the actual low-level SPI hardware. This permits the driver code for attached devices to port easily to other hardware, including a bit-banging design.
Below is an example of bit-banging the SPI protocol as an SPI master with CPOL=0, CPHA=0, and eight bits per transfer. The example is written in the C programming language. Because this is CPOL=0 the clock must be pulled low before the chip select is activated. The chip select line must be activated, which normally means being toggled low, for the peripheral before the start of the transfer, and then deactivated afterward. Most peripherals allow or require several transfers while the select line is low; this routine might be called several times before deselecting the chip.
Extensibility severely reduced when multiple slaves using different SPI Modes are required. Access is slowed down when master frequently needs to reinitialize in different modes.
The board real estate savings compared to a parallel I/O bus are significant, and have earned SPI a solid role in embedded systems. That is true for most system-on-a-chip processors, both with higher end 32-bit processors such as those using ARM, MIPS, or PowerPC and with other microcontrollers such as the AVR, PIC, and MSP430. These chips usually include SPI controllers capable of running in either master or slave mode. In-system programmable AVR controllers (including blank ones) can be programmed using a SPI interface.
The full-duplex capability makes SPI very simple and efficient for single master/single slave applications. Some devices use the full-duplex mode to implement an efficient, swift data stream for applications such as digital audio, digital signal processing, or telecommunications channels, but most off-the-shelf chips stick to half-duplex request/response protocols.
For high-performance systems, FPGAs sometimes use SPI to interface as a slave to a host, as a master to sensors, or for flash memory used to bootstrap if they are SRAM-based.
Although there are some similarities between the SPI bus and the JTAG (IEEE 1149.1-2013) protocol, they are not interchangeable. The SPI bus is intended for high speed, on board initialization of device peripherals, while the JTAG protocol is intended to provide reliable test access to the I/O pins from an off board controller with less precise signal delay and skew parameters. While not strictly a level sensitive interface, the JTAG protocol supports the recovery of both setup and hold violations between JTAG devices by reducing the clock rate or changing the clock"s duty cycles. Consequently, the JTAG interface is not intended to support extremely high data rates.
The SPI bus is a de facto standard. However, the lack of a formal standard is reflected in a wide variety of protocol options. Different word sizes are common. Every device defines its own protocol, including whether it supports commands at all. Some devices are transmit-only; others are receive-only. Chip selects are sometimes active-high rather than active-low. Some protocols send the least significant bit first.
SPI Bus was originally defined by Motorola. The original defining document was Motorola Application Node AN991. When Freescale spun out of Motorola, the responsibility for AN991 went with Freescale. When NXP acquired Freescale, NXP also acquired responsibility for AN991 which was last revised in January 2002 as AN991/D and still serves as the "official" defining document for SPI Bus.
Some devices have minor variances from the CPOL/CPHA modes described above. Sending data from slave to master may use the opposite clock edge as master to slave. Devices often require extra clock idle time before the first clock or after the last one, or between a command and its response. Some devices have two clocks, one to read data, and another to transmit it into the device. Many of the read clocks run from the chip select line.
Some devices require an additional flow control signal from slave to master, indicating when data is ready. This leads to a 5-wire protocol instead of the usual 4. Such a ready or enable signal is often active-low, and needs to be enabled at key points such as after commands or between words. Without such a signal, data transfer rates may need to be slowed down significantly, or protocols may need to have dummy bytes inserted, to accommodate the worst case for the slave response time. Examples include initiating an ADC conversion, addressing the right page of flash memory, and processing enough of a command that device firmware can load the first word of the response. (Many SPI masters do not support that signal directly, and instead rely on fixed delays.)
Many SPI chips only support messages that are multiples of 8 bits. Such chips can not interoperate with the JTAG or SGPIO protocols, or any other protocol that requires messages that are not multiples of 8 bits.
There are also hardware-level differences. Some chips combine MOSI and MISO into a single data line (SI/SO); this is sometimes called "three-wire" signaling (in contrast to normal "four-wire" SPI). Another variation of SPI removes the chip select line, managing protocol state machine entry/exit using other methods. Anyone needing an external connector for SPI defines their own: UEXT, JTAG connector, Secure Digital card socket, etc. Signal levels depend entirely on the chips involved.
There are a number of USB hardware solutions to provide computers, running Linux, macOS, or Windows, SPI master or slave capabilities. Many of them also provide scripting or programming capabilities (Visual Basic, C/C++, VHDL, etc.).
An SPI host adapter lets the user play the role of a master on an SPI bus directly from a PC. They are used for embedded systems, chips (FPGA, ASIC, and SoC) and peripheral testing, programming and debugging.
The key parameters of SPI are: the maximum supported frequency for the serial interface, command-to-command latency and the maximum length for SPI commands. It is possible to find SPI adapters on the market today that support up to 100 MHz serial interfaces, with virtually unlimited access length.
SPI protocol being a de facto standard, some SPI host adapters also have the ability of supporting other protocols beyond the traditional 4-wire SPI (for example, support of quad-SPI protocol or other custom serial protocol that derive from SPI
SPI protocol analyzers are tools which sample an SPI bus and decode the electrical signals to provide a higher-level view of the data being transmitted on a specific bus.
Most oscilloscope vendors offer oscilloscope-based triggering and protocol decoding for SPI. Most support 2-, 3-, and 4-wire SPI. The triggering and decoding capability is typically offered as an optional extra. SPI signals can be accessed via analog oscilloscope channels or with digital MSO channels.
When developing or troubleshooting the SPI bus, examination of hardware signals can be very important. Logic analyzers are tools which collect, analyze, decode, and store signals so people can view the high-speed waveforms at their leisure. Logic analyzers display time-stamps of each signal level change, which can help find protocol problems. Most logic analyzers have the capability to decode bus signals into high-level protocol data and show ASCII data.
A Queued Serial Peripheral Interface (QSPI; see also Quad SPI) is a type of SPI controller that uses a data queue to transfer data across the SPI bus.wrap-around mode allowing continuous transfers to and from the queue with only intermittent attention from the CPU. Consequently, the peripherals appear to the CPU as memory-mapped parallel devices. This feature is useful in applications such as control of an A/D converter. Other programmable features in QSPI are chip selects and transfer length/delay.
SPI controllers from different vendors support different feature sets; such DMA queues are not uncommon, although they may be associated with separate DMA engines rather than the SPI controller itself, such as used by Multichannel Buffered Serial Port (MCBSP).
Microwire,μWire, is essentially a predecessor of SPI and a trademark of National Semiconductor. It"s a strict subset of SPI: half-duplex, and using SPI mode 0. Microwire chips tend to need slower clock rates than newer SPI versions; perhaps 2 MHz vs. 20 MHz. Some Microwire chips also support a three-wire mode.
As mentioned, one variant of SPI uses a single bidirectional data line (slave out/slave in, called SISO or master out/master in, called MOMI) instead of two unidirectional ones (MOSI and MISO). This variant is restricted to a half duplex mode. It tends to be used for lower performance parts, such as small EEPROMs used only during system startup and certain sensors, and Microwire. Few SPI master controllers support this mode; although it can often be easily bit-banged in software.
For instances where the full-duplex nature of SPI is not used, an extension uses both data pins in a half-duplex configuration to send two bits per clock cycle. Typically a command byte is sent requesting a response in dual mode, after which the MOSI line becomes SIO0 (serial I/O 0) and carries even bits, while the MISO line becomes SIO1 and carries odd bits. Data is still transmitted msbit-first, but SIO1 carries bits 7, 5, 3 and 1 of each byte, while SIO0 carries bits 6, 4, 2 and 0.
Quad SPI (QSPI; see also Queued SPI) goes beyond dual SPI, adding two more I/O lines (SIO2 and SIO3) and sends 4 data bits per clock cycle. Again, it is requested by special commands, which enable quad mode after the command itself is sent in single mode.
Further extending quad SPI, some devices support a "quad everything" mode where all communication takes place over 4 data lines, including commands.Intel QuickPath Interconnect) or "serial quad I/O" (SQI)
Intel has developed a successor to its Low Pin Count (LPC) bus that it calls the Enhanced Serial Peripheral Interface Bus, or eSPI for short. Intel aims to allow the reduction in the number of pins required on motherboards compared to systems using LPC, have more available throughput than LPC, reduce the working voltage to 1.8 volts to facilitate smaller chip manufacturing processes, allow eSPI peripherals to share SPI flash devices with the host (the LPC bus did not allow firmware hubs to be used by LPC peripherals), tunnel previous out-of-band pins through the eSPI bus, and allow system designers to trade off cost and performance.
The eSPI bus can either be shared with SPI devices to save pins or be separate from the SPI bus to allow more performance, especially when eSPI devices need to use SPI flash devices.
This standard defines an Alert# signal that is used by an eSPI slave to request service from the master. In a performance-oriented design or a design with only one eSPI slave, each eSPI slave will have its Alert# pin connected to an Alert# pin on the eSPI master that is dedicated to each slave, allowing the eSPI master to grant low-latency service because the eSPI master will know which eSPI slave needs service and will not need to poll all of the slaves to determine which device needs service. In a budget design with more than one eSPI slave, all of the Alert# pins of the slaves are connected to one Alert# pin on the eSPI master in a wired-OR connection, which will require the master to poll all the slaves to determine which ones need service when the Alert# signal is pulled low by one or more peripherals that need service. Only after all of the devices are serviced will the Alert# signal be pulled high due to none of the eSPI slaves needing service and therefore pulling the Alert# signal low.
This standard allows designers to use 1-bit, 2-bit, or 4-bit communications at speeds from 20 to 66 MHz to further allow designers to trade off performance and cost.
All communications that were out-of-band of the LPC bus like general-purpose input/output (GPIO) and System Management Bus (SMBus) are tunneled through the eSPI bus via virtual wire cycles and out-of-band message cycles respectively in order to remove those pins from motherboard designs using eSPI.
This standard supports standard memory cycles with lengths of 1 byte to 4 kilobytes of data, short memory cycles with lengths of 1, 2, or 4 bytes that have much less overhead compared to standard memory cycles, and I/O cycles with lengths of 1, 2, or 4 bytes of data which are low overhead as well. This significantly reduces overhead compared to the LPC bus, where all cycles except for the 128-byte firmware hub read cycle spends more than one-half of all of the bus"s throughput and time in overhead. The standard memory cycle allows a length of anywhere from 1 byte to 4 kilobytes in order to allow its larger overhead to be amortised over a large transaction. eSPI slaves are allowed to initiate bus master versions of all of the memory cycles. Bus master I/O cycles, which were introduced by the LPC bus specification, and ISA-style DMA including the 32-bit variant introduced by the LPC bus specification, are not present in eSPI. Therefore, bus master memory cycles are the only allowed DMA in this standard.
eSPI slaves are allowed to use the eSPI master as a proxy to perform flash operations on a standard SPI flash memory slave on behalf of the requesting eSPI slave.
Not to be confused with the SDIO(Serial Data I/O) line of the half-duplex implementation of the SPI bus, sometimes also called "3-wire SPI-bus". Here e.g. MOSI (via a resistor) and MISO (no resistor) of a master is connected to the SDIO line of a slave.
"D25LQ64 1.8V Uniform Sector Dual and Quad SPI Flash" (PDF) (data sheet). version 0.1. GigaDevice. 11 February 2011. Archived from the original (PDF) on 12 February 2017. Retrieved 2017-02-10.
Enhanced Serial Peripheral Interface (eSPI) Interface Specification (for Client Platforms) (PDF) (Report). Revision 0.6. Intel. May 2012. Document Number 327432-001EN. Retrieved 2017-02-05.