; waitTest.asm
; WAIT, on a disk slow enough to be worth waiting for.
;
; Two reads, waited for rather than spun on, with INTERRUPTS MASKED and no handler
; installed anywhere. That is the shape this instruction exists for: a program sleeps on a
; device it has no handler for and reads the device's status when it wakes.
;
; THE SECOND READ IS THE TEST. A line that wakes the CPU without being dispatched has to
; be taken down by the WAIT itself; left standing, it is found by the next WAIT, which
; returns at once, and the program spins for the whole of the second read while looking
; exactly as though it slept. Both reads print, so a hang fails here - but a program that
; spun would print the same two characters, and what tells them apart is the emulator's
; count of idle cycles against bus cycles. Tests/terminal.sh is where that is checked,
; because settle() strips cycle counts out of every recorded output including this one.
;
; Written by Anachronaut

#Program
start:
  CIF
  INIA 0d3
  OUTA 0xE3
  INIA 0x20
  OUTA 0xE2
  INIA 0x03
  OUTA 0xE8
  RSTA
  OUTA 0x20
  OUTA 0x21
  INIA 0x01
  OUTA 0x22
  CALL waitDisk
  INIA 0x31             ; "1"
  OUTA 0x00
  RSTA
  OUTA 0x20
  INIA 0x01
  OUTA 0x21             ; Block 1, a different one.
  INIA 0x01
  OUTA 0x22
  CALL waitDisk
  INIA 0x32             ; "2"
  OUTA 0x00
  INIA 0x0A
  OUTA 0x00
  HALT

waitDisk:
  INA 0x23
  INIB 0x01
  AND
  BRQ waitDone
  WAIT
  BRI waitDisk
waitDone:
  RET
#Vectors
  Boot start