GS6150 Datasheet, PDF (40/64 Pages) Gennum Corporation – Automatic or Manual Rate Selection

The steps required for the application host processor to write to the Configuration and
Status Registers via the GSPI, are as follows:
1. Set Command Word for write access (R/W = 0) to the local registers 0h-80h; set Auto
Increment; set the Unit Address field in the Command Word to match the
configured DEVICE_UNIT_ADDRESS which will be zero. Write the Command Word.
2. Write the Data Word to be written to the first register.
3. Write the Data Word to be written to the next register in Auto Increment mode, etc.
Read access is the same as the above with the exception of step 1, where the Command
Word is set for read access (R/W = 1).
Note: The UNIT ADDRESS field of the Command Word must always match
DEVICE_UNIT_ADDRESS for an access to be accepted by the device. Changing
DEVICE_UNIT_ADDRESS to a value other than 0 is only required if multiple devices are
connected to a single chip select (in Loop-Through or Bus-Through configuration.)
GS6150
Final Data Sheet
PDS-060127
Rev.2
March 2015
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