Sending data to 634 LCD


New member
What is the best way to send data to from a basic stamp micro controller to a 634 lcd? They are both connected to a basic stamp breadboard. Where can I find code that will initialize the LCD?

Also, should data be sent in through the 'data_in' pin on the front?

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USB LCD Displays - Graphic and Character LCDs with a Keypad

CF Tech

If you have true RS-232 levels, then just feed it into the "Data_in" pin. If it is 0-5v levels, close JPE. If your signal is inverted (common for 0-5v levels) close JPB.

Also supply +5v to:

+5v (LCD)
+5v (LED)

and connect ground to "Ground".

No initialization is necessary. Send "Hello World" and it will show "Hello World".

CF Tech

Yes, there is a CFA-635 serial firmware version which brings the Rx & Tx out the back connector at "inverted logic levels". There is also a small PCB available that converts the levels to "true RS-232". You would have to email for a quote--it is a special order.