1739 - LatticeECP3 : What are the functions of register bits tdrv_drvcur_set and tdrv_amp_boost?

The register bits of LatticeECP3 tdrv_drvcur_set and tdrv_amp_boost are used to control SERDES differential output voltage. The register bit tdrv_drvcur_set sets the reference current of SERDES transmit driver. The register bit tdrv_amp_boost is used to boost transmit swing amplitude of SERDES transmit driver. When you use LatticeECP3 SERDES/PCS, you don't need to directly set these two register bits to achieve output swing amplitude. These register bits are controlled by the value assigned to the CHx_TDRV attribute in the Lattice IPExpress flow.

Refer to Table 8-13 of LatticeECP3 SERDES/PCS Usage Guide (tn1176.pdf) to obtain the relationship of output swing amplitude of SERDES/PCS with respect to the value of CHx_TDRV. The CHx_TDRV attribute supports nine values which define various differential output voltages between -4(640mV) and 4(1440mV). The value of attribute CHx_TDRV is assigned in the Differential Output Voltage of IPExpress as shown in Figure 8-22 of LatticeECP3 SERDES/PCS Usage Guide (tn1176.pdf).

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1739 - LatticeECP3 : What are the functions of register bits tdrv_drvcur_set and tdrv_amp_boost?

1739 - LatticeECP3 : What are the functions of register bits tdrv_drvcur_set and tdrv_amp_boost?

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4012 - [Lattice ECP3] PCI Express Endpoint Core IP: How does the Lattice PCIe (Peripheral Component Interconnect Express) IP core issue multiple MSI (Message Signaled Interrupts) when multiple MSI request bits are set in the end application?

6321 - CrossLink-NX: Why are there no exception constraints between the byte clock and pixel clock, e.g. set_clock_groups constraints for each clock in the IP LDC file?