Having issues getting a CFA633 ( =20
http://www.crystalfontz.com/product/CFA633-TMC-KS.html ) to do =20
anything (other than power up, display it's HW/FW versions, then do =20
nothing but look pretty).  I had picked this up from a member on this =20
this list a couple years ago, but never used it until now.  Hoping =20
someone has used this, or another of Crystalfontz's serial LCDs which =20
may/should have a similar protocol.

As a test I'm sending 0x06 (clear data), 0x00 (no data bytes will =20
follow), 0xA0 (CRC), 0x03 (CRC) with a small delay between these =20
bytes.  I've verified that's what's happening on the LCD-Rx line with =20
a logic analyzer.  But the display remains unchanged.  FWIW, I =20
calculated the CRC with an online CRC calculator and hard-coded it =20
into the code for now.

Hardware-wise, the display is setup to take RS232 signal levels, so I =20
dug up a 2-decades-old, but never used ICL232 DIP chip and wired it =20
up.  My analog scope shows a quick blip of digital pulses go by, and =20
hyperterminal with a RS232-to-USB adapter shows me a bunch of symbolic =20
characters, so I'm considerably assuming this chip works.

However, then I noticed a jumper reference near the end, which shows =20
there's another pair of jumpers to let the display use logic-level =20
serial signals.  All it says is:

JP11:  open: J1 (RS232), Pin 2 is open (see also JP2 and JP3).
        closed: Logic-level (0-5V) LCD Tx/Host Rx to J1 (RS232), Pin 2.

JP12:  open: J1 (RS232), Pin 3 is open (see also JP4 and JP5).
        closed: Logic-level (0-5V) LCD Rx/Host Tx to J1 (RS232), Pin 3.

FWIW, the other referenced pins are related to different positions on =20
the header connector that the RS232-level Rx/Tx pins can be on...

- JP2 (which I have closed) puts the LCD Tx on pin 2.
- JP3 (which I have open) puts LCD Rx on pin 2.
- JP4 (which I have closed) puts the LCD Rx on pin 3.
- JP5 (which I have open) puts Ground on pin 3.

There's no other reference to the logic-level signals that I could =20
find in the manual.  So I opened JP2 & JP6, closed JP11 & JP12, and =20
tried it, but still the same.  Either this LCD has a problem, or my =20
data is incorrect.

Anyone here able to suggest what could be wrong here?

Cheers,
-Neil.




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