> PCIe and SerDes Control and Status Registers
216
PEB383 User Manual
July 25, 2011
Integrated Device Technology, Inc.
Confidential - NDA Required
14.9.12
PCIe Control and Level Override Register
The register provides a method for overriding the value of TX_LVL, LOS_LVL, and ACJT_LVL in the
“PCIe Control and Level Status Register”
Register name: PCIE_CTL_OVRD
Reset value: Undefined
Register offset: 0x428
Bits
7
6
5
4
3
2
1
0
31
:
24
OVRD
TX_LVL
LOS_LVL
23
:
16
LOS_LVL
ACJT_LVL
15:08
Reserved
07:00
Reserved
Bits
Name
Description
Type
Reset
Value
31
OVRD
Override all level controls.
R/W
0
30:26
TX_LVL
Fine Resolution setting of Tx signal level.
Equation: Pk-Pk output level (without attenuation) = 1230 x
(48 + tx_lvl/2)/63.5 mV Vdiff-pp
Note: TX_LVL should be set to >= 0x1010 (which results in
an output of 1Vp-p). For more information on available
settings, see
R/W
0x10
25:21
LOS_LVL
Loss of Signal Detector level
R/W
0x10
20:16
ACJT_LVL
AC JTAG Receiver Comparator level
This sets the hysteresis level for AC JTAG. For information
on setting the correct voltage levels, see IEEE 1149.6.
R/W
0x10
15:0
ReservedP
Preserve state on writes.
R/W
Undefined
Table 39: TX_LVL Values
TX_LVL
Value
TX_LVL[0:4]
Vdiff-pp (mV)
0
0x00
5'b00000
929.8
1
0x01
5'b00001
939.4
2
0x02
5'b00010
949.1
3
0x03
5'b00011
958.8
4
0x04
5'b00100
968.5
5
0x05
5'b00101
978.2