SNIU028D February 2016 – September 2020 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138A , UCD3138A64
Up to 4 bytes can be read with the same number of firmware steps as 1 byte, taking advantage of the 4 byte TXBUF. Here is a sequence diagram for 4 bytes:
The steps are exactly the same as the sequence for 1 byte above, except that TX_COUNT needs to be 4 before TXBUF is written. Steps 6, 7, and 8 are the same for all reads, and will only be shown in the 1 byte case to reduce complexity on the longer message sequence diagrams.