IBM 4610 SureMark GR3, Дополнение к руководству по программированию

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5.0 Command Set Reference
A command consists of a string of data received from the serial communication link. The minimum length
of a command string is four byte; the maximum length depends on the command type.
The microcode checks that the length is not less than the minimum required for the command type specified
in byte 2. A command is composed of four parts:
1. Command Prefix
It consists of two constant bytes x
′1
B66
′ (
ESC f).
Command prefix is not present in system commands.
2. Command Code
Command code is in byte 2 of command string. It identifies the command to be executed.
Its value can range from x
′00′
to x
′
F F
′.
3. Command Extension
Command extension is in byte 3 of command string. It contains command options.
Reserved bits must be set to 0. Only exception is retry bit which is ignored by microcode on commands
where it has not any effect.
4. Command Data
Command data starts from byte 4 of command string. Its content depends on the command type.
Character strings must be left aligned.
Numeric strings must be right aligned.
Non significant digits in numeric fields can be blank.
At least one status is sent in response to a command.
The only exception is related to system commands: no response is given for system commands not
recognized by the fiscal unit.
The format of the status is described in 2.0, “Printer and Fiscal Unit Status” on page 19.
Note - 7 is the most significant bit and 0 is the least significant bit.
Command Set Reference — Page 45 of 183