C6747 mcasp data

Theo Chen,

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Since there is no C6767 device, at least one number in your title may be incorrect. Please tell us the correct part number for the device you are using. We can make guesses based on the document number for the McASP User's Guide, but I do not always guess correctly.

theo_chen said:

(1)the mcasp datasheet (sprufm1)  page 12 shows ,the slot size can be 8,12,16...32 and the word size can also be 8,12,16...32. But i can't  find any registers that can program the word size, and how does the mcasp counts the number of bits in a word /slot?

XMASK and RMASK determine the valid bits in a data word within a slot. Please search the User's Guide for XMASK, and in section 2.4.2.3.1 you will find a simple example of bit values of XMASK and which word sizes those correspond to.

theo_chen said:

(2)the mcasp datasheet (sprufm1)  page 28 shows, "once the entire slot iof data is collected in the XRSR, the data is copied to the data buffer XRBUF ", if  i use the slot size = 8 bits , and my word size is 8 bits , after this slot  is copied to XRBUF, what kind of data will be  in XRBUF ?

The 8 bits of the word size as defined by the RMASK register will be in the XRBUF.

theo_chen said:

(3)i use the AFIFO, i know the RFIFO's address is MCASP_0_DATA? so how about WFIFO?

Figure 28 shows where the WFIFO and RFIFO reside within the AFIFO module. The addresses of registers are device-specific, as stated at the beginning of Section 3, so I cannot tell you for certain what the address would be without knowing the correct device number. Possibly, both WFIFO and RFIFO are accessed at the same address.

Regards,
RandyP