HP TR3271 Programming Manual page 79

ZPROTO specifies the protocol to be used by the subdevice.
This required field must be assigned one of the following
values:
ZTR3-VAL-PROTO-CRT
ZTR3-VAL-PROTO-PTP
Refer to the Device-Specific Access Methods--AM3270/TR3271
manual for more information about these protocols.
ZRECSIZE specifies the maximum number of bytes the subdevice
can send or receive in a record.
The recommended record size depends on the protocol used and
the type of subdevice as follows:
CRT terminal
PTP subdevice
ZXPARENT is a Boolean value that controls transparent-text
mode for the named subdevice.
transparent-text mode is enabled for the subdevice; if the
value is ZSPI-VAL-FALSE, it is not.
VAL-FALSE. Transparent-text mode can only be enabled if the
TR3271 line is configured with the EBCDIC character set and
transparent-text mode enabled.
The CRT protocol will be used.
The pass-through protocol (PTP) will be
used
Use the defined screen size as the record
size. The record size is used for reference
only.
The TR3271 I/O process allocates the
buffer based on the value of this field.
Use the defined screen size as follows:
Screen Size
480
960
1920
2560
3440
3564
When using pass-through mode, the TR3271
subdevice should have the same record size
as the AM3270 subdevice that is on the
other end of the connection.
If the value is ZSPI-VAL-TRUE,
COMMANDS AND RESPONSES
This is a required field.
Record Size
512
1024
2048
3072
4096
4096
The default is ZSPI-
ADD Command
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