10. Registers > Lane Control Registers
CPS-1848 User Manual
436
June 2, 2014
Formal Status
This document is confidential and is subject to an NDA.
Integrated Device Technology
19:20
TX_SYMBOL_CTL This controls the slew rate of the transmitter.
0b00 = Slowest transitions
0b11 = Fastest transitions
Note: This field is recommended to be always set to 0b11.
RW
0b00
21:26
TX_AMP_CTL
Selects the local SerDes drive strength. Default is long run. The
low end of the long run range d’40. Short run nominal depends on
link speed. If above 5 Gbaud, short run nominal is d’28. If below
5 Gbaud, short run nominal is d’32.
Note: To enable write access to this field, set AMP_PROG_EN to
1 in the
RW
0b110100
27:28
TX_RATE
These bits in conjunction with the PLL_DIV_SEL bit in the
determine the transfer rate of the lane.
PLL_DIV_SEL = 0
0b00 = 1.25 Gbaud
0b01 = 2.5 Gbaud
0b1X = 5.0 Gbaud
PLL_DIV_SEL = 1
0b00 = RES
0b01 = 3.125 Gbaud
0b1X = 6.25 Gbaud
Default is configured with the value of the external SPD[1:0]
signals
Note: It is a programming error to set the value of this field
differently from the value of RX_RATE.
Note: The initial value of this field is determined by the setting of
the SPD[1:0] external pins.
Note: Before changing this field value, see
for the correct procedure to follow.
RW
Undefined
(Continued)
Bits
Name
Description
Type
Reset
Value