Transceiver RX Component Reset

Versal ACAP GTM Transceivers Architecture Manual (AM017)

Document ID
AM017
Release Date
2022-04-27
Revision
1.0 English

Transceiver RX component resets can be reset individually in either sequential mode or single mode. They are primarily used for special cases. These resets are needed when only a specific subsection needs to be reset.

Driving GTRXRESET from High to Low starts the component reset process. All RXPMARESETMASK and RXPCSRESETMASK bits along with RXRESETMODE must be held constant during the rest process.

When RXRESETMODE is set to sequential mode, the internal resets are toggled in sequence depending on the RXPMARESETMASK and RXPCSRESETMASK selection. When RXRESETMODE is set to single mode, the internal resets are toggled simultaneously depending on the RXPMARESETMASK and RXPCSRESETMASK selection.

In sequential mode, if the RX PCS is to be reset, RXUSERRDY must toggle High prior to the internal PCS reset signal being released, allowing RX reset to be completed.

Direct single reset ports EYESCANRESET, RXCDRRESET, RXPRBSCNTRESET, and RXPROGDIVRESET are available to perform single resets of the respective RX components. When direct single reset ports are toggled, a single reset is performed regardless of RXPMARESETMASK, RXPCSRESETMASK, and RXRESETMODE selection. These ports must be held Low during any sequential or single rests driven by GTRXRESET.

The following table lists the recommended receiver resets for common situations.

Table 1. Recommended Receiver Resets for Common Situations
Situation Components to be Reset Recommended RX Reset Setting
RXRESETMODE RXPMARESETMASK RXPCSRESETMASK
After power up and confirmation LCPLL, ILO, Entire RX 2'b00 8'b11111111 3'b111
After turning on a reference clock to the LCPLL/RPLL being used LCPLL, ILO, Entire RX 2'b00 8'b11111111 3'b111
After changing the reference clock to the LCPLL/RPLL being used LCPLL, ILO, Entire RX 2'b00 8'b11111111 3'b111
After assertion/deassertion of LCPLLPD or RPLLPD for the PLL being used LCPLL, ILO, Entire RX 2'b00 8'b11111111 3'b111
After assertion/deassertion of RXPD[1:0] Entire RX 2'b00 8'b11111111 3'b111
RX rate change RX PMA and RX PCS 2'b00 8'b11111111 3'b111
RX parallel clock source reset RX PCS 2'b00 8'b00000000 3'b111
After remote power up Entire RX 2'b00 8'b11111111 3'b111
Electrical Idle Entire RX 2'b00 8'b11111111 3'b111
After connecting RXN/RXP Entire RX 2'b00 8'b11111111 3'b111
After recovered clock becomes stable RX PCS 2'b11 8'b00000000 3'b010
After RX buffer status error RX PCS 2'b11 8'b00000000 3'b010
After changing channel bonding mode in real time RX PCS 2'b11 8'b00000000 3'b010
After PRBS error PRBS Error Counter 2'b11 8'b00000000 3'b100
Eye Scan reset only Eye Scan 2'b11 8'b00000000 3'b0001