SPRUJB3C March 2024 – November 2025 AM67 , AM67A , TDA4AEN-Q1 , TDA4VEN-Q1
The 64-bit TIME_STAMP can be adjusted by parts per million or by parts per hour. Writing a non-zero value to the CPSW3_CPSW_NU_CPTS_TS_PPM_LOW_VAL_REG[31-0] TS_PPM_LOW_VAL (Time stamp PPM Low value) and CPSW3_CPSW_NU_CPTS_TS_PPM_HIGH_VAL_REG[9-0] TS_PPM_HIGH_VAL (Time stamp PPM High value) enables PPM operations. The adjustment is up or down depending on the [7] TS_PPM_DIR bit in the CPSW3_CPSW_NU_CPTS_CONTROL_REG register. The TIME_STAMP value is increased by the PPM value when [7] TS_PPM_DIR bit is cleared. The TIME_STAMP value is decreased by the PPM value when [7] TS_PPM_DIR bit is set.
Parts Per Million example:
To adjust for 100 parts
per million the configured value for TS_PPM[41-0]
(through
CPSW3_CPSW_NU_CPTS_TS_PPM_LOW_VAL_REG[31-0]
TS_PPM_LOW_VAL and
CPSW3_CPSW_NU_CPTS_TS_PPM_HIGH_VAL_REG[9-0]
TS_PPM_HIGH_VAL) is:
1,000,000/100 = 10,000(decimal)
Parts Per Hour example:
To adjust for 1 part
per hour at 1 GHz CPTS_RFT_CLK the configured
value for TS_PPM[41-0] (through
CPSW3_CPSW_NU_CPTS_TS_PPM_LOW_VAL_REG[31-0]
TS_PPM_LOW_VAL and
CPSW3_CPSW_NU_CPTS_TS_PPM_HIGH_VAL_REG[9-0]
TS_PPM_HIGH_VAL) is:
(1,000,0000,000Hz/1pph) * (3600 seconds/hour) =
34630B8A000 (hex)