Using 2, CFA634-NFA-KS displays with SPI


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My new project is using two CFA634-NFA-KS. I am using the SPI interface with the Basic Stamp 2px (see attached) Both displays turn on, display the "Crystalfontz" welcome screen then blank with a flashing cursor in the upper left corner. Neither display responds to the sample BS2 program (see attached).

1. Both displays are configured with Jumpers A and E closed (TTL, Low Speed SPI) Is this correct?

2. Does the schematic seem OK?

3. Can you suggest some lower level commands that would help me troubleshoot the interface?

4. Any other suggestions would be appreciated.

p.s. these are beautiful displays... nice "big print" version for those who don't wear their reading glasses all the time :)

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I think your code should be:


You are specifying the chip select as the data pin in your SHIFTOUT statement.

Also, judging by the SPI timing info in the data sheet, chip select must be taken high between each byte to synchronize the bits. I don't think the SHIFTOUT statement can control the chip select, so you probably have to use a separate SHIFTOUT statement for each byte of a string (along with the CS low and CS high statements).
USB LCD Displays - Graphic and Character LCDs with a Keypad


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Oh noo.... I feel really dumb now! Thanks I'll try that tonight. I bet it will work. -Scott