additional info needed when using sainsmart st7735 tft

[RD2RTG]

Hi,

First of all, i really appreciate the effort you have put in creating these drivers. I am doing a pet project to drive st7735 sainsmart 1.8 inch tft using stm32f103c8T6 minimum system eval board off amazon. The following is the pin breakout on that tft. Last 4 are for sd-card and has to be controlled by a seperate SPI hardware. So leave them be for now. I am trying to connect rest of the pins to the stm32 SPI2 as per the pin breakout in the comments for main.c . VCC,GND,CS,SDA and RESET are pretty straight forward but do you know where SCL and RS/DC should go according to your diagram??

GND : Power Ground
VCC : 5V power input
CS : Chipselect for LCD,
SDA : LCD Data for SPI
SCL : SCLK for TFT Clock
RS/DC : Command/Data Selection
RESET : LCD controller reset, active low


CS (SD-CS) : Chipselect for TF Card,
CLK (SD-Clock): SPI Clock
MOSI (SD-DI) : SPI Master out Slave in
MISO (SD-DO) : SPI Master in Slave out

[illis]

Just currently messing around trying to get this to work with libopencm3. Got it somewhat working with some cheap 128x128 screen. Still having issues with clears not filling the entire screen, and red showing up as blue and vice versa.

SCL == SCK (PB13 if your using SPI2)
I think RS/DC maps to A0 in this code (

st7735_spi_stm32/st7735.h

Line 51 in 89c4e23

// ST7735 A0 (Data/Command select) pin

) (PA11 by default).

Lemme know how you get on.

[illis]

Ignore my comment about the blue <-> red thing -- http://cal-eng.com/?page_id=981. Just need to swap channels.

[illis]

Also just fixed my issue with not filling the entire screen - just needed to add some calibration tweaks to the ST7735_AddrSet function (prob is a better way somewhere).

[RD2RTG]

Hi illis. Thanks for the response. I got some time to work with it few weeks ago. Yes RS/DC goes to A0 and SCL is SCK. Using this code i was running into some wierd issues. I can print stuff on the screen now but only with 5x7 functions at 2x magnification. I see some unrecognizable scribbles with 5x7 1x, 7x11 1x and 2x . I havent tried any pictures yet on this display. I will try to get some snapshots of screen displays for various conditions and upload them here.

[illis]

@RD2RTG One thing that springs to mind, could be the initization settings for the display - as there are a few variants (black/red/green/... tabs). I think I compared my init strings with some from here: https://github.com/adafruit/Adafruit-ST7735-Library/blob/master/Adafruit_ST7735.cpp#L138