AK4955 Datasheet, PDF (79/117 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/SPK/Cap-less VIDEO-AMP/ LDO & DSP

[AK4955]
■ Checksum Function
The AK4955 has a checksum function. When SUMRSTN bit = “1”, checksum of writing data is updated. When
SUMRSTN bit = “0”, the checksum value is rest to zero. Checksum is calculated in 8-bit step. When the checksum value
exceeds 255 in decimal format, the values will be subtracted by 256. Checksum value can be monitored by reading
CSUM7-0 bits. This function is only valid in 3-wire control mode (I2C pin = “L”).
Access to the AK4955
SUMRSTN
=“0”
Checksum= 0
=“1”
Write Command?
Read
Checksum Not Updated
Write
Updating Checksum
Figure 73. Flowchart of Checksum
MS1343-E-00
- 79 -
2011/12