APPLICATION NOTE 7.12
Software Identification of the COM20020 Rev B, Rev C and Rev D
By Rich Wahler
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. This is accomplished by interrogating register 5 as
described below.
To identify the COM20020 Revision follow the following procedure:
1. Write 0xFF to Register 5
2. Read Register 5
• If the value read from Register 5 is 0x7F then the part is a COM20020 Rev B or earlier
• If the value read from Register 5 is 0x0F then the part is a COM20020 Rev C
• If the value read from Register 5 is 0x8F then the part is a COM20020 Rev D
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