![]() The Sainsmart display had an ADS7843 controller, which is supported by the same Linux driver: ads7846.Įarlier I had extended the FBTFT SD-image with a modified ads7846 driver that can add it's own device. I already had some experience with the ITDB02-2.8 display which had a TSC7846 touch controller. The last step was to get the touchpanel to work. With the FBTFT SD-image it is very easy to do driver development: Īnd the flexfb driver can handle a lot of displays without the need for a dedicated driver: I encourage people writing framebuffer drivers for these small displays, to try the FBTFT project. Add section to Kconfig and Makefile and finally add the device to fbtft_device.Ī little fight with the init code to get rotation working though. Just copy the itdb28fb driver, change all occurences of itdb28fb to sainsmart32fb, add initialization sequence and set_addr_win function. The next step was to make a dedicated driver for this display: sainsmart32fb. I will look more into this later, when I'm done documenting what I've done so far. This post indicates that we could use speeds between 16 and 32MHz. It was a bit disappointing that I couldn't drive the display at 32MHz. ![]() The flexfb driver was extended to support the SSD1289, and in minutes I had a working display. Spritemods had already made a framebuffer driver for this LCD controller, so I copied the initialization sequence from him. So with a reboot the SPI bus was working properly. I had to reboot the computer! I haven't done any investigation into why it behaves like this. It took me some time to find out that after the script had used the SPI bus lines as GPIOs, I couldn't just reload the SPI controller driver spi_bcm2708. I needed to know that the circuit worked before I went on with the driver. I really get into trouble when there's alot of wires on the breadboard, so I had to write a script to test the circuit. Well, documentation isn't really that much fun, so I skipped ahead and extended the breadboard circuit to try it with my Sainsmart 3.2" display which has a 16-bit bus. The plan was to make an 8-bit protoboard, do some more testing and write documentation, but then my soldering iron died on me. So, I started small and tested the circuit on the ITDB02-2.8 display which has an 8-bit bus, and that worked fine at 32Mhz. Spritemods circuit needs the next byte to latch in the current data. Other LCD controllers doesn't support this.Īnother benfit is that my circuit gives a completed transfer. * The circuit uses CS to latch the data into the LCD controller. * Using SPI for the control signals cuts the bandwidth in half. ![]() But I wanted a different interface circuit than the one used in that thread. I have wanted to add support for this controller to my project for a long time. 320x240 LCD with integrated SSD1289 controller is the most viewed non HDMI/RCA thread in the Screens and displays forum. ![]()
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