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Update Embedded Masted with "Non-TFT version SPI LCD interface" problems


#1

Hello,

I have a Embedded Masted with "Non-TFT version SPI LCD interface"
I have updated the board with the last “GHI Loader” and as reported in your
pdf document the LCD is not supported.

“SPI-Based Displays: Except for CANxtra, EMX firmware does not natively support
SPI-based LCDs (the ones used with the old non-TFT Embedded Master Modules
based devices such as non-TFT Embedded Master Development System), but
users can still use graphics feature and refresh the LCD from the managed code
over SPI bus. GHI is providing a simple example how to accomplish this process.
CANxtra SPI LCD is natively supported.”

Well, The board works fine but I have some problem to drive the SPI2 channel
to manually update the LCD.
As reported in your pdf document I have used the following lines to drive the SPI2

Pin Name Description
12 LCD_RST Default pin for LCD reset
18 LCD_CMD Default pin for LCD command/data select
46 LCD_SSEL (SPI2) LCD salve select
51 LCD_MISO (SPI2) LCD master in slave out (usually not used)
48 LCD_SCK (SPI2) LCD serial clock
49 LCD_MOSI (SPI2) LCD master out slave in

My code is based on your sample named “Graphical128x64Display”,
it’s the code that I wrote:

SPI.Configuration spiconfig = new SPI.Configuration((Cpu.Pin)SelectPin, true, 100, 100, false, true, 1000, SPIModule);
_RST = new OutputPort((Cpu.Pin)ResetPin, true);
_DC = new OutputPort((Cpu.Pin)CommandPin, true);

_spi = new SPI(spiconfig);
	
where:

SPIModule   is SPI2
SelectPin   is 46
ResetPin    is 12
CommandPin  is 18

when I created the “new SPI(spiconfig)” I got an ArgumentException

If I try the code with SPI1 channel the code work fine

SPIModule   is SPI1
SelectPin   is 39
ResetPin    is 12
CommandPin  is 18

Where is my mistake ?
Have you an example to drive the 128x64 LCD with SPI2 to send to me ?

Regards

Mirco Vanini


#2

Where did you get these pins numbers?
"SelectPin is 46"
But old EMM non TFT only had 45 I/Os

Please see free ebook for example on driving SPI LCDs.


#3

I was looking at the old PDF.
"46 E33/P0.6/LCD_SSEL*"
The 46 is the module pin number. 33 is the IO number…
This is quite old, maybe it is time to upgrade :wink: