Initialization - Oki ML420 Maintenance Manual

2.1.3 Initialization

This printer is initialized when the power is turned on or when the I-PRIME-N signal is input
from the host side via the parallel interface.
For the initialize operation, the RST-N signal is first output from the reset circuit to reset the
MPUs and LSIs. When resetting ends, the program starts and the LSIs are reset by MPU via
LSIRST-N. Reset operation by I-PRIME starts program to initialize, but does not reset the MPU.
The program here sets the mode of the LSI including the MPU, checks the memories (ROMs
and RAMs), then carries out carriage homing, and determines the LF motor phase.
Finally, the program establishes the interface signals (P-I/F: ACK-P signal sending, and S-I/F:
BUSY-N signal off) and lights the SELECT lamp to inform the ready state for receiving to the
host side and ends the initialize operation.
42113901TH01 Rev.3
MPU RESET
Initial Setting
Internal RAM
CHECK
ROM CHECK
LSI RESET
LSI Initial Setting
and I/F Busy ON
External RAM
CHECK
RAM Clear
LF Motor Phase
Initialization
Carriage Homing
Serial
I/F
I/F BUSY OFF
Start
MPU
I/F ACK Send
End
Oki Data CONFIDENTIAL
Parallel
I/F
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