This document provides a programming reference for the SN75LVPE3410 Quad-Channel PCI-Express Gen-3 Linear Redriver. It contains detailed information related to the SN75LVPE3410 advanced configuration options. The intended audience includes software engineers working on system diagnostics and control software.
TI recommends that the reader be familiar with the SN75LVPE3410 data sheet (SNLS737).
The SN75LVPE3410 supports register control through the Serial Management Bus (SMBus).
In a typical system, SMBus access is used to configure the device and monitor the device status.
The SN75LVPE3410 internal registers can be accessed through standard SMBus protocol. The SMBus secondary address is determined at power up based on the configuration of the EQ1_ADDR1 and EQ0_ADDR0 pins. The pin state is read on power up, after the internal power-on reset signal is deasserted.
The EQ1_ADDR1 and EQ0_ADDR0 pins along with GAIN, VOD, EN_SMB, and RX_DET pins are 4-level input pins that are used to control the configuration of the device. These 4-level inputs use a resistor divider to help set the four valid levels as shown in Table 1-1.
Pin Level | Pin Setting |
---|---|
L0 | 1 kΩ to GND |
L1 | 13 kΩ to GND |
L2 | Float |
L3 | 59 kΩ to GND |
There are 16 unique SMBus secondary addresses that can be assigned to the device by placing external resistor straps on the EQ0_ADDR0 and EQ1_ADDR1 pins as shown in Table 1-2. When multiple SN75LVPE3410 devices are on the same SMBus interface bus, each device must be configured with a unique SMBus secondary address.
EQ1_ADDR1 Pin Level | EQ0_ADDR0 Pin Level | 7-Bit Address [HEX] | 8-Bit Write Address [HEX] |
---|---|---|---|
L0 | L0 | 0x18 | 0x30 |
L0 | L1 | 0x19 | 0x32 |
L0 | L2 | 0x1A | 0x34 |
L0 | L3 | 0x1B | 0x36 |
L1 | L0 | 0x1C | 0x38 |
L1 | L1 | 0x1D | 0x3A |
L1 | L2 | 0x1E | 0x3C |
L1 | L3 | 0x1F | 0x3E |
L2 | L0 | 0x20 | 0x40 |
L2 | L1 | 0x21 | 0x42 |
L2 | L2 | 0x22 | 0x44 |
L2 | L3 | 0x23 | 0x46 |
L3 | L0 | 0x24 | 0x48 |
L3 | L1 | 0x25 | 0x4A |
L3 | L2 | 0x26 | 0x4C |
L3 | L3 | 0x27 | 0x4E |