Renesas SH7781 - Manual (Page 1322)

25. Audio Codec Interface (HAC)
Rev.1.00 Jan. 10, 2008 Page 1292 of 1658
REJ09B0261-0100
Read codec
No
Yes
No
Yes
No
Yes
Yes
Yes
Yes
No
Yes
RegV = H'7C
(Vender ID1)
Last_Reg: Address of the register
read last time
Dummy read
Dummy processing
(Discard the first data)
Read_codec_aux (RegN)
RegN = Last_Reg?
Error
Data return
Error
Error
Error
Error
Error
Error
Error Data 2 return
Read_codec_aux
Send_read_request (RegN)
Send_read_request (RegN)
Get_codec_data (RegN)
Get_codec_data (RegN)
Read_codec_aux (RegV)
No
No
No
Error
: Data acquisition
: Data 1 acquisition
: Data 2 acquisition
Input: RegN (address of the codec register to be read)
Input: RegN (address of the codec register to be read)
In continuous reading of registers in some off-chip codec
devices, the data in the register previously read may be read
again. In such case, take the steps in this flowchart.
Figure 25.5 Sample Flowchart for Off-Chip Codec Register Read (1)