ep.hobbyiest Posted April 25, 2017 Report Share Posted April 25, 2017 Hi, I was looking for GUI solution last time, But due to other work i suspended this one. I have Discovery board STM32F411. I want to display some temperature and some data. So, I want to use 5 inch with resistive touch. Not fast refresh required, but screen loading should not be display. Few screens might be there. So, I have following doubt. 1. Is SPI interface will be suitable for my application? 2. Which TFT lcd Controller is compatible with STM32 and ugfx i should use? 3. Do i require extra memory if screen's are more than 6? Mostly i will be using Text only. Link to comment Share on other sites More sharing options...
inmarket Posted April 25, 2017 Report Share Posted April 25, 2017 1. SPI will be fine provided the display resolution is not too high. The higher the redolution the higher the bandwidth you need to update it at a reasonable speed. 2. On the uGFX website there is a list of controllers that are supported. Any supported controller will work with STM32. 3. You will need RAM for a framebuffer only if your chosen display controller does not have internal RAM for the framebuffer. In practice all SPI and 8 bit parallel controllers will have internal RAM for the framebuffer. 16bit controllers may or may not depending on the controller. Link to comment Share on other sites More sharing options...
Joel Bodenmann Posted April 26, 2017 Report Share Posted April 26, 2017 13 hours ago, inmarket said: 1. SPI will be fine provided the display resolution is not too high. The higher the redolution the higher the bandwidth you need to update it at a reasonable speed. That is of course correct. But whenever possible, go parallel. However, if done wrong this can actually be slower than SPI. Have a look at this goodie: Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted April 26, 2017 Author Report Share Posted April 26, 2017 ohh... yes. I don't want to face this problem. We can go with parallel method(8/16-bit). Then which kind of inexpensive lcd's are used here mostly. I tried last time 3.2 inch lcd which got blown out(without making it work). following type lcd's i found (Without criteria) http://www.winstar.com.tw/products/tft-lcd/module/5-tft-lcd.html http://www.buydisplay.com/default/tft-5-inch-lcd-display-module-controller-board-serial-i2c-ra8875 http://www.buydisplay.com/default/5-tft-lcd-display-module-wvga-800x480-high-resolution-for-mp4-gps http://www.buydisplay.com/default/lcd-5-inch-display-480x272-tft-module-touch-screen-for-mp4-gps Link to comment Share on other sites More sharing options...
Joel Bodenmann Posted April 27, 2017 Report Share Posted April 27, 2017 14 hours ago, ep.hobbyiest said: We can go with parallel method(8/16-bit). Just make sure that you hook it up properly. Don't hesitate to ask if in doubt. All but the second display that you linked appear to only provide an RGB interface. That's not what you want unless you want to / can use the LTDC peripheral of the higher-end STM32 lines. Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted April 29, 2017 Author Report Share Posted April 29, 2017 (edited) yes, right i dont want to use RGB interface board. But how about other display http://www.buydisplay.com/default/5-tft-lcd-display-module-wvga-800x480-high-resolution-for-mp4-gps http://www.buydisplay.com/default/lcd-5-inch-display-480x272-tft-module-touch-screen-for-mp4-gps Are they good? Does anyone interface this/similar display's ? Do you know any dev board or other board? So, i can test the display and later i can go for my own pcb. I have discovery stm32f411 board. Edited April 29, 2017 by ep.hobbyiest Link to comment Share on other sites More sharing options...
Alvin Posted April 29, 2017 Report Share Posted April 29, 2017 I don't think there's that many good options for a 5inch display. Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted April 29, 2017 Author Report Share Posted April 29, 2017 1 hour ago, Alvin said: I don't think there's that many good options for a 5inch display. Which option are you talking about? Link to comment Share on other sites More sharing options...
David Kibble Posted May 2, 2017 Report Share Posted May 2, 2017 Is cost the main concern for you and do you have stringent real time constraints? If not - maybe look at other embedded Linux boards such as those from Olimex (a20, a13 etc). These boards offer a huge amount of processing power and memory along with good i/o and various LCD interfaces including direct RGB for a reasonable price and size. I've used the A20 and A13 along with RGB 4.3" and 5" 800x480 LCDs from China alongside uGFX. The BuyDisplays LCDs are pretty good in my experience (have used 2.8" SPI + 4.3" RGB models). Touch screens work fine with uGFX as they use the Linux touch driver included by Olimex in their Debian build. The great thing with these types of embedded Linux boards is you can easily move from testing on your Linux PC to the real hardware with good confidence things will work exactly the same. Yes there are some odd differences, but it's a much easier road in my experience compared with truly dedicated hardware. Just an idea in case you are not wedded to the STM32. Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted May 4, 2017 Author Report Share Posted May 4, 2017 Hi, Thanks for the great solution. Cost: I am mainly looking for availability and in that cost. I am not looking for cheaper solution nor more costly. 4.3 inch will work for me. I am using STM32 in my project and i never work on linux board before. So, i am preferring STM32 controller. I don't have dedicated board to start work on GUI. I have other board, But for beginner it would be better to have working things to get some confidence. Link to comment Share on other sites More sharing options...
Joel Bodenmann Posted May 5, 2017 Report Share Posted May 5, 2017 Take one of these SSD1963 based ones and hook it up to the FSMC interface of your STM32 and you'll be fine: http://www.buydisplay.com/default/tft-display/5-inch Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted May 7, 2017 Author Report Share Posted May 7, 2017 (edited) SSD1963 this gonna take some time for shipping. Now, I can try with SSD1289. Edited May 7, 2017 by ep.hobbyiest Link to comment Share on other sites More sharing options...
phofman Posted May 7, 2017 Report Share Posted May 7, 2017 I am working on integrating the inexpensive 4.63" LCD https://www.aliexpress.com/item/4-63-inch-16-9-272-480-TFT-screen-with-Resistance-touch-and-PCB-panel-LCM/32802272563.html with chibios on STM32F103, will report when finished. Link to comment Share on other sites More sharing options...
ep.hobbyiest Posted May 9, 2017 Author Report Share Posted May 9, 2017 On 5/8/2017 at 01:29, phofman said: I am working on integrating the inexpensive 4.63" LCD https://www.aliexpress.com/item/4-63-inch-16-9-272-480-TFT-screen-with-Resistance-touch-and-PCB-panel-LCM/32802272563.html with chibios on STM32F103, will report when finished. That's great. Let me know where i can help. And i will do it parallely as well. Link to comment Share on other sites More sharing options...
phofman Posted May 9, 2017 Report Share Posted May 9, 2017 I am working on init sequence - trying to reconcile the ugfx driver init sequence (very likely comes from a different device, some registers are not present in ILI9481, e.g. 0xc4) and the sequence supplied by the vendor. By the end of this week I hope to try running the LCD. Link to comment Share on other sites More sharing options...
inmarket Posted May 10, 2017 Report Share Posted May 10, 2017 Always try the existing code first before playing with the init sequence as there are commonly things not mentioned in the datasheets. Also sometimes extra code has been added to handle clone chips (which can be very hard to distinguish from the original physically). Only change the init sequence if it doesn't work for you and even then change it as little as possible to get it to work. Link to comment Share on other sites More sharing options...
phofman Posted May 10, 2017 Report Share Posted May 10, 2017 (edited) Hi inmarket, I very much appreciate you help. This is what I found out. The code was kindly provided by Abhishek in commit https://git.ugfx.io/dongie/uGFX/commit/b2252bb7bede275461700db9c56b702a93a33982. Please note the ILI9481 or compatible. Abhishek describes his project on his blog https://theembeddedkitchen.net/author/abhishek/page/2 where he says Quote ... It uses the Renesas R61581 TFT controller, which is an enhancement of the ILITek ILI9481 originally used in such displays (the instruction set is nearly compatible).... ...The R61581/ILI9481 drivers adapted for this board have been contributed by me to the uGFX project.... R61581 datasheet http://www.allshore.com/pdf/Renesas_R61581.pdf shows exactly the codes found in the existing gdisp_lld_ILI9481.c - 8 parameters of register (ILI9481 has only six), first parameter of 0xc0 has options in bits 2:0, fitting the 0x03 value (unlike ILI9481 which has zeros there), register 0xc4 (not present in ILI9481). Clearly this is driver for R61581 which is slightly different to ILI9481. Honestly, this has helped a lot to me since now I know how to handle it. Thanks, Pavel. Edited May 10, 2017 by phofman Link to comment Share on other sites More sharing options...
phofman Posted May 10, 2017 Report Share Posted May 10, 2017 Yes, works great with the ili9481 init sequence :-)! Link to comment Share on other sites More sharing options...
phofman Posted May 10, 2017 Report Share Posted May 10, 2017 inmarket, please how would you like the patch? I think the existing driver could be renamed to R61581 and I can send the working ILI9481 driver incl. support for 8bit transfer. Link to comment Share on other sites More sharing options...
inmarket Posted May 10, 2017 Report Share Posted May 10, 2017 I would love the patch. You can either attach it as a zip file in this forum or send a pull request on the repo. I will make sure it all gets updated in the master repo. Link to comment Share on other sites More sharing options...
phofman Posted May 11, 2017 Report Share Posted May 11, 2017 I will prepare the patch, after testing the register reading code. Please, will you rename the existing driver first, or should I include the rename in my patch set? Thanks. Link to comment Share on other sites More sharing options...
inmarket Posted May 11, 2017 Report Share Posted May 11, 2017 We will handle that. Thanks. Link to comment Share on other sites More sharing options...
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