Oki ML490 Maintenance Manual page 26

Power ON
Write instruction for IC reset 1
IC write for LED data,
2
etc.
Read instruction for
3
data read
4
NO
Response check
for OK or NG
YES
Error notification
5
Instruction for
retransmission
6
1
OPTXD
OPCLK
OPRXD
OPCLR-N
Reset
within IC
7
8
2 3
bit0 bit7
Command (first)
bit0 bit7
Command response (first) Command response (second)
Note
6
2
3 1 5 or 8
7
Command (second)