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z80

How do I do bcalls in hex?


So I have a TI-84 Plus C Silver Edition. I just started working on writing assembly programs on it using the opcodes. I found a good reference chart here, but was wondering how to do bcalls, specifically how to print a character to the screen. It seems as if the hex code for the call is 3 bytes long, but call takes in 2 bytes. So how do I call it? Also, does anyone know the memory location programs are loaded into when they are run for my calculator? I haven't been able to find it yet.


Solution

  • Based on the definitions here: http://wikiti.brandonw.net/index.php?title=84PCSE:OS:Include_File , a "bcall" is a RST 28 instruction followed by the specific number of the bcall. So to print a character you would do (given that PutC is 44FB):

    rst 28h
    dw 44FBh
    

    Presumably the character to print is in A register.