Command/Status Transmission And Reception Procedure - Oki B6100 Technical Manual

Principles of Operation

Command/Status Transmission and Reception Procedure

The MCU never voluntarily sends a status. The MCU sends a status only as a response to a command that
is sent by the Controller. After the Controller sends a command, it does not send another command until it
receives a response from the MCU.
•
One byte command:
The printer returns status N*, which corresponds to the header code of the received command.
•
Multiple byte command:
Multiple byte commands are transmitted in separate bytes. The printer determines the length of the
command from information presented in the header code, and returns status 0 in response to each
header and the following bytes, except the last byte. After the last byte is received, the printer returns
a status N* which corresponds to the header code.
•
Command errors
The MCU checks the received command for three types of errors. If the MCU detects an error, it
returns an Error status. When the Controller receives the Error status, it retransmits the command.
•
"Undefined" error
•
"Incorrect use" error
•
"Parity" or "Framing" error
• Status errors
If the MCU returns a status error, and the Controller is in the middle of transmitting a multiple byte
command, the Controller ignores the status error and completes the transmission. If the Controller
receives a status error in response to a command (except status 0), the Controller can retransmit the
command and declare a fault only after a set number of error returns. The action of the Controller is
determined by the specifications of the Controller software.
13-48 OKI B6100 Laser Printer - Base Engine Technical Manual
engine po040FA
engine po041FA
Version 1.0