all repos — xyw @ f9db54986add6293b8bea565ec774c09a442e75b

A minimal virtual machine and assembler for terminals.

examples/on-error.xyw

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.include "devices.xyw" 

; register on error handler
on_error system.on_error STW

; main program
$10 $0 DIV
end JMPw

; on error handler
.label on_error
    system.error LDB $1 EQU on_error.div-by-zero.print JCNw
    unknown-error print JSRw
    $0 system.error STB
    RTS
    .label on_error.div-by-zero.print
        div-by-zero-error print JSRw
        $3 system.error STB
        RTS

; printing subroutine
; a16 --
.label print
  POPxw
  .label print.loop
    LDBxw terminal.output STB
    INCxw LDBxw print.loop JCNw
    CLRxw
    RTS

.label div-by-zero-error
.string "Error: Division by zero.\n"
.label unknown-error
.string "Error: Unknown error.\n"
.label end