SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
The TS_GENFn output cycle can be adjusted by parts per million (PPM) or by parts per hour (PPH). Writing a non-zero CPTS_PPM_LOW_REG_j/CPTS_PPM_HIGH_REG_j value enables PPM operations. The PPM counter continually loads and decrements to zero and then loads again. A single RCLK adjustment is made when the PPM counter decrements to zero. The adjustment is up or down depending on the CPTS_CONTROL_REG_j[0] PPM_DIR bit. When PPM_DIR is set a single RCLK time is subtracted from the generate function counter which has the effect of increasing the generate function frequency by the PPM amount. When PPM_DIR is clear a single RCLK time is added to the generate function counter which has the effect of decreasing the generate function frequency by the PPM amount.