Reading loop values from digital monitor requires a clock on port CH[1/2/3/4]_DMONITORCLK along with setting attributes TESTCON, COE_EN, SELMINI, TESTEN, and TESTC. In GTM transceivers, each adaptation loop can be monitored in parallel through dedicated read-only registers.
For example, to read the values for adaptation loops KH, KL, and AGC for channel 0, set the following attributes:
- 0x0C65[20:17] =
4'b0000 - 0x0C65[16] =
1'b1 - 0x0C95[28] =
1'b0 - 0x0C98[17] =
1'b1 - 0x0C98[16:15] =
2'b00
Use the following read-only registers to monitor KH, KL, and AGC for
channel 0:
- 0x0899[15:8]
- 0x0899[7:0]
- 0x089A[15:8]
- 0x089A[7:0]
- 0x089B[15:8]
- 0x089B[7:0]