Int 17 Fn C0  - PC Magazine Pcspool - Get Control Block Address            [c]

   AH = C0h
   DX = printer port (0-3)

Return: ES:BX -> control block (see below)

See Also: AH=C1h

Format of control block:
Offset Size    Description
 00h   WORD    printer number
 02h   WORD    address of printer status port
 04h   WORD    number of first record in queue
 06h   WORD    number of last record in queue
 08h   DWORD   characters already printed
 0Ch   DWORD   number of characters remaining
 10h   DWORD   pointer to dequeue buffer
 14h   DWORD   previous count of characters printed
 18h   DWORD   number of clock ticks taken to print them
 1Ch   WORD    offset of next character to output
 1Eh   WORD    offset of next character to print
 20h   WORD    pointer to spooling queue record
 22h   BYTE    current spooling status
 23h   BYTE    current printer status:
       00h OK
       01h not ready
       02h paused with message
       03h paused
       04h initializing
       FEh non-existent port
       FFh not spooled
 24h   BYTE    current control record type
 25h   WORD    observed printer speed
 27h   WORD    characters to print per service
 29h   BYTE    01h if disk write needed
 2Ah   BYTE    01h if queued data should be flushed
 2Bh   BYTE    01h to update cps status