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Using Nextion 7" as a profile creator using touch draw and coordinates

I have a screen I want to use to input a ramp/soak pattern by drawing it on screen , I have touch press set to thdra=1 and touch release set to sendxy=1 , here is a picture of the screen , I have it setup as a hotspot ? do I need to do that ? 

I am going to send this data to a file to create a profile for Ramp/soak. 

the problem : the numbers I get back make no real sense some of them seem to be random ? , the top left of the screen is supposed to be 0,0 right ? when I touch a spot I get weird numbers that do not seem right . if I touch on the bottom left I get this , I know the format from other post and manual. 103 is ID etc. 


103

0

76

1

182

0

255

255

255

101

5

1

0

255

255

255

ramp soak.png
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I am using Arduino Uno to read the serial data BTW 

Alright I found that the screen is cut up !! from top to CENTER is 0-255 then it repeats !! from 255-0 WTH ? same with side to side but that seems to repeat 3x's 

my graph area is 800x480 full screen maybe a bug ? or am I doing something stupid ? 

Did you check the raw output? Are both the 'X High-order+Coordinate' and 'Y  High-order+Coordinate' always zero?
0X67++ Coordinate X High-order+Coordinate X Low-order+Coordinate Y High-order+Coordinate Y Low-order+TouchEvent State+End


They dont seem to be ,heres me touching top left  top rt ,bot rt, bot left coord's  , can you explain High order vs low order ? is it 100 vs less than 100 ? not a programmer here in case you didnt figure that out ! 

 


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The raw output starts with 0x67, then there is X-high, X-low, Y-high, Y-low and then 0xff 0xff 0xff

It is described at https://www.itead.cc/wiki/Nextion_Instruction_Set

Check the raw output.

Mike,


Since your display is greater that 255 pixels in any direction, the co-ordinates cannot be represented by a single byte, therefore the co-ordinates are represented by two bytes (i.e a 16bit word). However these are still sent as two bytes - HIGH ORDER:LOW ORDER. You need to capture both of these bytes and convert to decimal, and the easiest way to do this is multiply the high order by 256 then add the low order.


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I have checked the raw output and it changes Maze ! 

Jon THANKS !!! that now makes sense !! I did not know it was limited to 255 or 256 ? 

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