Auto-Calibrate before Rotate

[jethronull]

It's nice having the FT800 run calibration automatically the first time and then remembering the data.  But what about when you need to rotate the screen?  The auto-calibration runs before you can make the REG_ROTATE call, so now the calibration is upside down for the screen.  Does anyone know a way to make the rotate call before the auto-calibration, or read and reverse the calibration data, or test for calibration data and use that to force calibration if needed, ?

I know I could probably make the rotation change in the GD2 library and avoid all this hassle but I like to keep libraries standard.

Also, what's the difference between self_calibrate and cmd_calibrate, if any?

TIA

[jamesbowman]

I think this should work, it's really just the code copied out of GD.begin().


   GD.begin(~GD_CALIBRATE);  // initialize but do not calibrate
   
   GD.wr(REG_ROTATE, 0);

   if (EEPROM.read(0) != 0x7c) {
     GD.self_calibrate();
     for (int i = 0; i < 24; i++)
       EEPROM.write(1 + i, GD.rd(REG_TOUCH_TRANSFORM_A + i));
     EEPROM.write(0, 0x7c);  // is written!
   } else {
     for (int i = 0; i < 24; i++)
       GD.wr(REG_TOUCH_TRANSFORM_A + i, EEPROM.read(1 + i));
   }


[jethronull]

That looks exactly what I need, thanks. Unfortunately it doesn't like GDTR reference. I see it defined as Static in GD2.cpp. Can it be moved or duplicated in my code to make this work?

TIA

[jamesbowman]

Aha yes... I changed the GDTR references to GD in the original post.

[jethronull]

Got it. Just one more prob (I think): I modified GD.begin(~GD_CALIBRATE) to GD.begin(~GD_STORAGE | ~GD_CALIBRATE) so that I could keep the startup reliable (remember I don't have SD support), but that doesn't work as expected. Before this new rotation/calibration mod the ~GD_STORAGE had worked a charm on keeping startup reliable (that and the ConnectEve has a Power Down line which I toggle on power up). But it doesn't seem to want to work with ~GD_CALIBRATE. Depending on which way round they are (I think) I either still get the FT800 calibration or very iffy boots.

[jamesbowman]

GD.begin() takes a bitmask. The default is to initialize everything. So to switch off calibration:

GD.begin(~GD_CALIBRATE);
and to switch off storage:

GD.begin(~GD_STORAGE);
and to switch off both:

GD.begin(~(GD_STORAGE | GD_CALIBRATE));

or equally:

GD.begin(~GD_STORAGE & ~GD_CALIBRATE);
by De Morgan's.

[jethronull]

Perfect, I doff my cap to you sire.

[jum]

Thanks, I used the rotated screen code above because after I had built the Gamediuno 2 into my project box I found the screen was upside down (doh!).

Note that I had to force the self_calibration the first time by temporarily replacing:

if (EEPROM.read(0) != 0x7c) {

with

if (true)

(as the 0x7c had already been written by a previous calibration)

[hala]

regards
I want to make the calibration of FT800 automatic. I use arduino IN PROGRAMMING
whats is the code I should use instead of FTImpl.Cmd_Calibrate(0);

[jamesbowman]

The equivalent for GD2 is "GD.self_calibrate()"

Here is the code you can use instead of GD2.begin(), which stores or loads the calibrations:

 GD.begin(~GD_CALIBRATE);
 GD.wr(REG_ROTATE, 0); // flip the display 180 degrees
 if (EEPROM.read(0) != 0x7c) {
   GD.self_calibrate();
   for (int i = 0; i < 24; i++)
     EEPROM.write(1 + i, GD.rd(REG_TOUCH_TRANSFORM_A + i));
   EEPROM.write(0, 0x7c);
 } else {
   for (int i = 0; i < 24; i++)
     GD.wr(REG_TOUCH_TRANSFORM_A + i, EEPROM.read(1 + i));
 }


[hala]

my code in arduino ,, when using your code i got error

[hala]

I found this code in library but I can't define the correct values I should use so I don't know if this code is right
FT_Trans::Write(REG_TOUCH_ADC_MODE,AdcMode);
FT_Trans::Write16(REG_TOUCH_CHARGE,Charge);
FT_Trans::Write(REG_TOUCH_SETTLE,Settle);
FT_Trans::Write16(REG_TOUCH_OVERSAMPLE,Oversample);
FT_Trans::Write(REG_TOUCH_RZTHRESH,RZTreshold);