Other Parts Discussed in Thread: UCD90160, UCD9090
D8h - Run Time Clock Trim is not supported by UCD90320. How is the Run Time Clock supposed to be trimmed on this device?
We are using the UCD90320 on a new product. But our existing products use ucd9090(A) and ucd90160(A). So I'm testing the Run Time Clock Trim on a UCD9090 because the ucd TS drifts considerably from the system clock. In the case that I'm testing, I find that a +/-2% change adds or subtracts ~312ms if adjusted every 30 seconds. A +/-1% change adds or subtracts ~5ms. But a +/-0.5% change adds or subtracts ~142ms. Here are the values written to D8h
-2% - 0xc600
-1% - 0xB402
-0.5% 0xac00
+0.5% - 0xb200
+1% - 0xb3fe
+2% - 0xbbff
Why does it appear that the change doesn't linearly follow the percentage value?
The User Guide doesn't provide much guidance. Is there additional documentation or guidance to trim the run time clock?
Is it expected that trim adjustments need to made continuously or just one or a few times?
