How to change communication?


New member

I have a LCD module 12232F (some chinese brand) with a ST7920 controller. I need to use the serial interface of the controller but the only thing I can find is:

System interface
ST7920 supports 3 kinds of bus interface to MPU. 8 bits parallel, 4 bits parallel and clock synchronized serial
interface. Parallel interface is selected by PSB=”1” and serial interface by PSB=”0”. 8 bit / 4 bit interface is selected by function set instruction DL bit.

I hardly think strapping into the 23:rd bonding pad of the controller is the best way of changing comminication mode. How is it usually done? Anyone, any ideas?

Does anyone have any code for init and control of the serial interface? I plan to connect a PIC to this one and I need to use this module because I need the built in character set but I also need to save pins on the PIC.

best regards
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CF Tech

You would only be able to change the LCD controller's communications mode if the module designer has brought out the P/S signal from the controller to a jumper or a pin. (We did that on our CFAX series . . . )