|The usual PICAXE interface to a serial LCD display is at 2400 baud, using any
available output pin. It's possible to use the more common 9600 baud interfaces from
a PICAXE 18A (and probably other chips that support setfreq). Using setfreq m8
provides 9600 baud output from the sertxd command. It should be obvious that
this only works if you are not using serial out for another purpose and if changing
the clock frequency does not affect other functions being used (pause, etc).
The LCD117 page has the full command set for the driver. You can set the display format (2x24, 4x20, etc), define a custom startup message of up to 4 lines of 20 characters, etc.
The code for talking the controller at 9600 baud is simple:
setfreq m8 'to get 9600 baud for LCD serial input sertxd("?f") 'clear LCD screen setfreq m4 'normal speed for other operations
For multiple commands:
setfreq m8 'Set cursor to line 0, position 10, display value in variable Counter, 'add a ":", display value in register b0, tab to the next position - 'writing a value to a specific screen location each time it's updated sertxd("?y0?x10",#Counter,":",#b0,"?t") setfreq m4
If you need to keep the PICAXE clock frequency constant, the newest version of the K107 board has an option to use the LCD108 chip from Peter Anderson to provide a 2400 baud interface.
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