Oki OKIPAGE 10ex Maintenance Manual page 248

B-21 Data sent through the centronics I/F cannot be received.
• Is the signal at Pin 11 (BUSY-P) of the connector (CENT) low?
• Yes
• Yes
• Yes
B-22 Cover open occurs frequently.
• Are Pins 2 and 3 of the diode D501 open?
• No
• Yes Failure of IC1 (MHM2029-004K).
40990901TH Rev.1
• No Is the signal at Pin 3 (PBUSY-P) of IC11 (7407) change at data
reception as shown below?
PBUSY-P
• No Failure of IC1 (MHM2029-004K).
• Yes Replace IC11 (7407).
Is the level of the signal at Pin 1 (PSTB-N) of the connector (CENT) change
at data reception?
• No Verify the connection of I/F cable or the operation of the host
computer.
Are the signals at Pin 5 (PACK-N), Pin 13 (PERROR-N) of IC11 (7407)
respectively low and high in on-line mode?
• No Replace IC11 (7407).
• Has the problem been solved?
• Yes End.
• No
Failure of IC1 (MHM2029-004K).
• Yes Replace D501.
Is the connection of the connector (POWER), correct?
• No Replace the connector (POWER).
ON-LINE OFF-LINE
Low High
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