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Basic 632 LCD Help


New member
I'm trying to print to the 632 LCD via RS232/DB9 from a microcontroller that has RS232 output.

I am able to print to the LCD fine from WinTest and HyperTerminal on my PC.

I am also able to print and communicate fine between the microcontroller and the PC/Hyperterminal. So in other words, the microcontroller is sending the right bits/characters.

However, I cannot print correctly from the microcontroller to the LCD. I am able to power the LCD on from external DC power. When I try to print a simple character like 'A' to the LCD, I get out a character corresponding to '}' or another high character. It is also not consistent in its printing. Sometimes an 'A' is a '{'. Other times it might be an up arrow.

Any ideas?
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Is the uart in your micro set for 7 (or 6 or 5) bit operation?
Slightly wrong baud rate?
So in other words, the microcontroller is sending the right bits/characters.
When you send control characters (less than 0x20 [\032]) from the micro, how do they appear in Hyperterm?

Are you sending any control chars from the micro to the 632, or only printable chars?

Hard to tell whats going on without some diagnostic tools (scope, serial analyser, etc).

CF Support2

Another thing to take a look at is the output of your Micro. The signal is commonly inverted on many micro controllers. The CFA632 can receive using normal or inverted signals. JPB on the module controls this. The module is shipped with this jumper open for "normal" operation and it is closed if you need inverted.

The CFA632 is fairly sensitive to baud rate as well. If different characters are being displayed over what you are sending it is often a symptom of a baud rate mis-match.
USB LCD Displays - Graphic and Character LCDs with a Keypad