Texas Instruments TMS320TCI6486 User Manual
Page 24
EMAC Functional Architecture
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Table 10. EMAC and MDIO Signals for RGMII Interface (continued)
Signal Name
I/O
Description
RGRXCTL
I
Receive control (RGRXCTL). The receive control data has the receive data valid (MRXDV) signal on
the rising edge of the receive clock, and a derivative of receive data valid and receive error
(MRXER) on the falling edge of RGRXC.
When receiving a valid frame with no errors, MRXDV = TRUE is generated as a logic high on the
rising edge on RGRXC and MRXER = FALSE is generated as a logic high on the falling edge of
RGRXC.
When no frame is being received, MRXDV = FALSE is generated as a logic low on the rising edge
of RGRXC and MRXER = FALSE is generated as a logic low on the falling edge of RGRXC.
When receiving a valid frame with errors, MRXDV = TRUE is generated as a logic high on the rising
edge of RGRXC and MRXER = TRUE is generated as a logic low on the falling edge of RGRXC.
RGMDCLK
O
Management data clock (RGMDCLK). The RGMDIO data clock is sourced by the MDIO module. It
synchronizes MDIO data access operations done on the RGMDIO pin. The frequency of this clock is
controlled by the CLKDIV bits in the MDIO control register (CONTROL).
RGMDIO
I/O
Management data input output (RGMDIO). The RGMDIO pin drives PHY management data into and
out of the PHY by way of an access frame consisting of start of frame, read/write indication, PHY
address, register address, and data bit cycles. The RGMDIO pin acts as an output for everything
except the data bit cycles, when the pin acts as an input for read operations.
RGMII pins are not multiplexed with other interfaces and are HSTL I/O having voltages different than other
interfaces. (RGMII pins are 1.5-V/1.8-V HSTL I/O, whereas other interfaces are 3.3-V LVCMOS I/O). The
unused pins of the RGMII PHY should be pulled down to avoid floating inputs.
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C6472/TCI6486 EMAC/MDIO
SPRUEF8F – March 2006 – Revised November 2010
Copyright © 2006–2010, Texas Instruments Incorporated