Grass Valley VM 3000 System Controllers v.7.4 - Manual (Page 726)

ASCII Protocol
N−2 VM 3000 Installation and Operating Manual
LLLLLLL −−−> Router Switcher LEVELS. This corresponds with a logical position in this ASCII port’s CP
Level Set. The range is from 1 to 7. For example, 1 refers to the first entry in the CP Level
Set, and 5 refers to the fifth entry in that same set. If no levels are specified, then the take is
assumed to apply to all levels defined in that set. Level number entries are NOT position−de-
pendent.
ASCII General Purpose Commands
ZA Acknowledge This command is used to see if the ASCII interface exists
and is running. A response of ZA is returned whenever a
ZA is received.
ZZ Reset This command forces the ASCII controller to reset. This
causes the interface to cancel all previous ZP, ZV, and
ZW commands. A ZX response is returned to the external
computer upon command completion. This ZX is also
returned whenever the interface is manually reset.
ZY Command Accepted This response is returned after the serial port has
(ACK) successfully parsed the command and in the case of a
switch command has successfully issued the TAKE to the
system and received a switch response back from the sys-
tem. This does NOT mean that the command was success-
fully executed. The remote computer should not issue a
new command until receiving a ZY or ZN from the cur-
rent command. The amount of time for the response will
vary depending on system complexity and current system
activity. Also the number of switches involved in the com-
mand will affect the amount of time it takes to receive the
ZY response. Multiple switches sent in one command
may result in ZR response(s) being returned before the
ZY response.
ZN Command Rejected A ZN will be issued when a condition occurs where
(NAK) the current command cannot be executed. A ZN response
can be issued for several reasons such as an invalid com-