COM20020D Datasheet, PDF (72/72 Pages) SMSC Corporation – ULANC Revision D Universal Local Area Network Controller with 2K x 8 On-Board RAM

APPENDIX C
Software Identification of the COM20020 Rev B, Rev C and Rev D
In order to properly write software to work with the COM20020 Rev B, C and D it is necessary to be
able to identify the different revisions of the part.
To identify the COM20020 Revision follow the following procedure:
1. Write 0x98 to Register-6 (Address = 6)
2. Write 0x02 to Register-5 (Address = 5)
3. Read Register-6
* If the value read from Register-6 is 0x98 then the part is a COM20020 Rev B or earlier
* If the value read from Register-6 is 0x9A then go to next step below
4. Write 0x80 to Register-5
5. Read Register-5
* If the value read from Register-5 is 0x00 then the part is a COM20020 Rev C
* If the value read from Register-5 is 0x80 then the part is a COM20020 Rev D
© 1998 STANDARD MICROSYSTEMS CORPORATION (SMSC)
Circuit diagrams utilizing SMSC products are included as a means of illustrating typical applications; consequently complete information
sufficient for construction purposes is not necessarily given. The information has been carefully checked and is believed to be entirely
reliable. However, no responsibility is assumed for inaccuracies. Furthermore, such information does not convey to the purchaser of
the semiconductor devices described any licenses under the patent rights of SMSC or others. SMSC reserves the right to make
changes at any time in order to improve design and supply the best product possible. SMSC products are not designed, intended,
authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury
or severe property damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or
modification will be fully at the risk of the customer.
COM20020D Rev. 11/9/98