PICaxe 18M WJEC Assembler

A sample program shows a delay instruction.

Is that in a header file that gets included when you choose 18M WJEC Assembler in devices?

Are there other handy features there too?
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Technical Support
Staff member
Effectively, but it's all handled behind the scenes by the compiler itself and there is not a header file as such. The following page details what instructions, predefined constants and 'assumed subroutines' are available for WJEC Assembler -


By the way; the WJEC assembler is for the 18M2 only, not the earlier 18M.


Technical Support
Staff member
In my opinion there is not much usefulness in learning or using WJEC assembler unless one is undertaking a course of study which requires it. It is rather limited in its utility and not the best choice for programming a PICAXE for a real project.

You would be better off learning PICAXE Basic or coding with Flowcharts or Blockly. You may also find it better to choose a 20M2 or 14M2 rather than the 18M2 because ports and pins are somewhat better placed for those chips. A 20X2 is a drop-in replacement for the 20M2 if higher execution speed is required.