
Registers
1408
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Serial ATA (SATA) Controller
Table 28-38. Port PHY Control Register (P0PHYCR) Field Descriptions (continued)
Bit
Field
Value
Description
30
OVERRIDE
Override for Clock Stopping. Normally the functional clock can only be stopped if the link is put into
Partial or Slumber power mode. However, if there is no device attached (such as in a removable
media situation) you may wish to stop the functional clocks but not be able to enter a low-power
state. In this case, software can set the OVERRIDE bit to 1, removing the requirement for a low-
power state.
CAUTION
When there is a device attached and the OVERRIDE
bit is used, if the functional clock is stopped when
the link is not in a low-power state may ruin the link
and cause undetermined behavior. A port reset or
full SATASS reset may be required to recover.
0
Normal
1
Override
29-26
Reserved
0
Reserved.
25-22
TXDE
0-Fh
Transmitter De-Emphasis. Selects 1 of 16 output de-emphasis settings from 0 to 71.42%
Reduction
%
dB
0
0
0
1
4.76
-0.42
2h
9.52
-0.87
3h
14.28
-1.34
4h
19.04
-1.83
5h
23.8
-2.36
6h
28.56
-2.92
7h
33.32
-3.52
8h
38.08
-4.16
9h
42.85
-4.86
Ah
47.61
-5.61
Bh
52.38
-6.44
Ch
57.14
-7.35
Dh
61.9
-8.38
Eh
66.66
-9.54
Fh
71.42
-10.87
21-19
TXSWING
0-7h
Transmitter Output Swing. Selects 1 of 8 output amplitude settings between 125 and 1375 mV
(dfpp).
0
125
1h
250
2h
500
3h
625
4h
750
5h
1000
6h
1250
7h
1375
18
TXCM
Transmitter Common Mode. Adjusts the common mode to suit the termination at the attached
receiver.
0
Normal Common Mode
1
Raised common mode. Common mode raised by 5% of e54.