User`s manual

Encoder Operation The encoder executes commands received one at a
time. When the encoder receives a command, it
performs the requested action and reports the re
-
sult. The printer cannot execute a new encoder
command until the previous encoder command has
been completed. Detailed encoder (and general
printer) status information is reported to the host via
optional serial interface ports only. See Appendix B
for a detailed listing of printer and encoder re
-
sponses.
Write The encoder, in default configuration, can write in
the forward or reverse directions and then automat
-
ically perform a write-verify data read. The printer
then repositions the card to the print-ready position.
Note that for ISO encoding, the Encoder attaches
the Start, Stop, and LRC characters, which should
not appear in the data sent.
Read The encoder can only read (back to the host) a sin-
gle track of data at a time. The “&L” command per-
forms read-only operations, see Command
Reference, page 2-67.
The “M or m” multiple commands can serve to
group several read commands. The encoder per-
forms each command in the string until command
string is completed. An error terminates an “M”
Command string, while command execution re-
sumes with error correction for an “m” command
string. The “M” command concatenates the read
data into a single response to the host.
Example of Multiple Read Command String
(Escape and Carriage Returns not shown)
Track 1 data = 1111
Track 2 data = 2222
Track 3 data = 3333
Multiple read command string is:
M 1 &L1[&L2[&L3
Data sent to the host, in a single response:
111122223333
C-2 980081-001 Rev. F