IDT CPS-1848, User Manual

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9. Reset and Initialization > Initialization
CPS-1848 User Manual 194 June 2, 2014
Formal Status This document is confidential and is subject to an NDA.
Integrated Device Technology
9.2.3 Register Initialization
To initialize the CPS-1848’s registers, complete the following steps in the order indicated:
1. Disable a port using one of the following steps:
a. Disable a port before it is reconfigured by register changes (see Port {0..17} Control 1 CSR .PORT_DIS).
b. Disable a port if a link partner is not expected to be present on the link (see Port {0..17} Control 1 CSR .PORT_DIS). A
port should be placed in port-lockout if a new link partner may appear on the link (see Port {0..17} Control 1
CSR .PORT_LOCKOUT).
2. Change the lane to port mapping if the required mapping is different from the configuration pin settings (see Lane to Port
Mapping ).
3. Change the lane to port speed setting if the required setting is different from the configuration pin settings (see Lane and
Port Speeds ).
a. Change the speed per-lane using Lane {0..47} Control Register [TX_RATE and RX_RATE].
b. Change the PLL speed using the PLL {0..11} Control 1 Register .
c. Reset the PLLs using the Device Reset and Control Register .
4. Configuration (no ordering is required for the following steps).
a. Program the route table as described in Programming Examples .
b. (Revision A/B only) Change Port {0..17} Lane Synchronization Register [VMIN] to 0b001 for 5 Gbaud or higher.
c. Change Port Link Timeout Control CSR [TIMEOUT] to a recommended value of 20–50 us (see Computing Timeout
Values ).
d. Enable all counters and error management as displayed in the following table (this is an optional step).
Steps 1a, 4 d, and 5 are not required if register initialization is taking place through an EEPROM.
Read/Write Offset Value Purpose
The following writes will configure CPS-1848’s counters and error management for all ports.
Write 0xF4FF04
Broadcast Port Operations
Register
0x0640_0070 • Sets CNTRS_EN = 0b1 and SILENCE_CTL =
0b101
• Enables PORT_LOG_EN, LANE_LOG_EN,
and LT_LOG_EN logging
Write 0x03FF04
Broadcast Port Error Report
Enable Register
0x807E_8037 Enables reporting of various error types for all
ports
Write 0xFD0008
Error Log Match Register {0..7}
0x0078_0000 Records and counts all errors, flag
The following reads are of the CPS-1848’s error logs.
Read 0xFD002C
Error Log Events Register
XXXX_XXXX Identifies the number of errors that occurred
Read 0xFD0004
Error Log Data Register
XXXX_XXXX Identifies the error source, group, and number.
To determine which error occurred, see
Error
Log Event Source Encoding .