National Instruments Printer Accessories 320030-01 Manual Do Utilizador

Página de 246
Table 4-5.  Auxiliary Commands:  Detail Description (continued)
Command Code
(COM4-COM0)
  4  3  2  1  0
Description
   0   0   0   0   1
Clear Parallel Poll Flag
   0   1   0   0   1
Set Parallel Poll Flag
These commands set the Parallel Poll Flag to the value of COM3.
The value of the Parallel Poll Flag is used as the local message
ist when bit four of Auxiliary Register B is zero.  The value of
SRQS is used as the ist when ISS=1.
   1   0   0   0   0
Go To Standby
The Go To Standby command  sets the local message gts if the
TLC is in Controller Active State (CACS) or when it enters CACS.
When the TLC leaves CACS, gts is cleared.
   1   0   0   0   1
Take Control Asynchronously
The Take Control Asynchronously command pulses the local
message tca.
   1   0   0   1   0
Take Control Synchronously
The Take Control Synchronously command sets the local message
tcs.  The local message tcs is effective only when  the TLC is in
Controller  Standby State (CSBS) or Controller Synchronous Wait
State (CSWS).  The local message tcs is cleared when the TLC
enters Controller Active State (CACS).
   1   1   0   1   0
Take Control Synchronously on END
The Take Control Synchronously on END command sets the local
message tcs when the data block transfer End message (END bit
equal to one) is generated at CSBS.  The tcs message is cleared
when the TLC enters CACS.
   1   0   0   1   1
Listen
The listen command generates the local message ltn in the form of
a pulse.
   1   1   0   1   1
Listen in Continuous Mode
The Listen in Continuous Mode command generates the local
message ltn in the form of a pulse and places the TLC in
continuous mode.
(continues)