Initialization - OKIDATA ML590 Service Manual

Page: 52
Service Guide ML590/ML591
Chapter 2 Principles of Operation

2.1.03 Initialization

This printer is initialized when the printer is powered on or when the I-PRIME-N signal is input
from the host via the parallel interface.
Printer Initialization occurs as listed below.
The RST-N signal is output from the Reset circuit to reset the MPU and LSIs.
The program is executed and the LSIs are reset by the MPU via IORST-N.
Note: A Reset operation initiated by I-PRIME does not reset the MPU.
The program sets the LSI (02D) mode, checks the memory (ROM/RAM), then executes carriage
homing and determines the phase of the line feed motor.
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 indicate that the printer is in the ON-LINE
state.