Oki 4M - Manual (Page 114)

B - 4
c) Data sending timing (nibble mode)
ACKNOWLEDGE
BUSY
6 7 4 5 2 3
DATA bit 3 DATA bit 7
FAULT
6 7 4 5 2 3
DATA bit 0 DATA bit 4
SELECT
. , - * +
DATA bit 1 DATA bit 5
PAPER END
& ' . $  , - "  * +
DATA bit 2 DATA bit 6