Oki Microline 520 Service Handbook page 211

4.1.02 Printer Serial Number Identification
To identify the revision level of a printer, record the serial number from the back of the printer.
Refer to the following to decode the serial number.
Example Printer Serial Number: 401A0154693
Date Code
Revision
Serial Number
4.1.03 Firmware Revision Identification
To identify the revision level and part number of the firmware, print the Rolling ASCII Test or
the Font Test.
Refer to Section 4.8 of this Service Handbook for information on printing the tests.
Header
At the top of the test is a header.
This header provides the following information: printer model (1), emulation (2),
country (3), firmware revision level (4), firmware part number (5) and character
generator revision number (6). This information is often required while performing
service or when contacting Okidata. Have this information available during your service
call.
1
ML520 EI A
Microline 520/521 Service Handbook
P/N 59257803
401 (4 = year. 01 = month)
A
0154693
3
2
4
F/W 01.22
CG 01.02
6
4 - 3
5
YR4084-xxxx-xx
Failure Analysis