dynamic selection of the chip

[infrafast]

Hello, I face the situation to have 2 possible ST7735 chip: with or without "S" at the end of the reference depending on supplier.

I understand I have to change the setting file to use the one best fitting the need, and it works //#define ST7735_INITB //#define ST7735_GREENTAB

define ST7735_GREENTAB2 //for ST7735

//#define ST7735_GREENTAB3 // #define ST7735_GREENTAB128 // For 128 x 128 display // #define ST7735_GREENTAB160x80 // For 160 x 80 display (BGR, inverted, 26 offset) // #define ST7735_REDTAB //for ST 7735S //#define ST7735_BLACKTAB //#define ST7735_REDTAB160x80 // For 160 x 80 display with 24 pixel offset

This has however to be done static when compiling the code.

2 questions / requirement proposal: 1) is there a way to query the chip and see which one equiped the board, so I would have something like getChip() 2) and/or Is there a way or a chance to do the chip selection dynamically during run time using a function such setChip(...) to abvoid having comoiling the code for each of them ?

The use case is that there are many device in the field, some of them are with the S , some of them are not ...

Thanks for your thought and possible fix that may go in that direction

[Bodmer]

Yes, for ST7735 only this is possible. See here: https://github.com/Bodmer/TFT_eSPI/blob/master/TFT_eSPI.h#L391

[infrafast]

thank you! I've commented all line related to the model in User_setup.h //#define ST7735_INITB //#define ST7735_GREENTAB //#define ST7735_GREENTAB2 //for ST7735 //#define ST7735_GREENTAB3 // #define ST7735_GREENTAB128 // For 128 x 128 display // #define ST7735_GREENTAB160x80 // For 160 x 80 display (BGR, inverted, 26 offset) // #define ST7735_REDTAB //for ST 7735S //#define ST7735_BLACKTAB //#define ST7735_REDTAB160x80 // For 160 x 80 display with 24 pixel offset

then change my call to init() to tft.init(INITR_GREENTAB2); // I used to use ST7735_GREENTAB2 for ST7735 and ST7735_REDTAB for ST7735S

maybe I miss something but it has no effect, it looks like it keep using the same code no matter I call init with one colorcode or another... did I miss a #define or something ? Thanks for your feedback

[infrafast]

sorry to bother, any chance to review the above mentionned issue?

[Bodmer]

It works OK for me. Are you using the Arduino IDE?

You still need to declare the display driver type in your setup file, so do not comment that out:

#define ST7735_DRIVER

The different tab colour init sequences are selected here by the tabcolor defined in the init(), so you can add debug print lines to test if the correct sequences are being invoked. e.g. like this:

...
       if (tabcolor == INITR_GREENTAB)
       {
         Serial.print("INITR_GREENTAB");
         commandList(Rcmd2green);
         colstart = 2;
         rowstart = 1;
       }
       else if (tabcolor == INITR_GREENTAB2)
       {
         Serial.print("INITR_GREENTAB2");
         commandList(Rcmd2green);
         writecommand(ST7735_MADCTL);
         writedata(0xC0 | TFT_MAD_COLOR_ORDER);
         colstart = 2;
         rowstart = 1;
       }
...

Since I cannot reproduce it I think you need to try to debug the problem.

[infrafast]

Thanks, I've added the debug info into the code. It shows that the flow goes thru the proper tabcolor condition.

After few tests, I realized that when you use the init function with patameter, you have to uncomment all the one you may need (in my case both ST7735_GREENTAB and ST7735_REDTAB) in the user_setup.h , otherwise it doesnt work. maybe you can add a comment in that sense into the code as at the moment it says:

// Comment out ALL BUT ONE of these options for a ST7735 display driver, save this // this User_Setup file, then rebuild and upload the sketch to the board again:

//#define ST7735_INITB //#define ST7735_GREENTAB

define ST7735_GREENTAB2 //for ST7735

//#define ST7735_GREENTAB3 // #define ST7735_GREENTAB128 // For 128 x 128 display // #define ST7735_GREENTAB160x80 // For 160 x 80 display (BGR, inverted, 26 offset)

define ST7735_REDTAB //for ST 7735S

//#define ST7735_BLACKTAB //#define ST7735_REDTAB160x80 // For 160 x 80 display with 24 pixel offset

Thanks again for your efficient support!

[Bodmer]

Glad to here it is working now. I still do not understand why it did not work for you initially, the color tab settings in the setup file should not matter as they are over-ridden by the tab color in the init() no matter which ones are commented or not commented out!

The tab colour selection via the init() is an undocumented feature and was just added for on request to solve a user problem. Hopefully I will get time to document it at a future date!

The good news is that it is working for you!