SPRS825F October 2012 – June 2020 F28M36H33B2 , F28M36H53B2 , F28M36P53C2 , F28M36P63C2
PRODUCTION DATA.
The individual EMAC and Management Data Input/Output (MDIO) signals for the MII interface are summarized in Table 5-58.
SIGNAL | TYPE(1) | DESCRIPTION |
---|---|---|
MIITXCK | I | Transmit clock. The transmit clock is a continuous clock that provides the timing reference for transmit operations. The MIITXD and MIITXEN signals are tied to this clock. The clock is generated by the PHY and is 2.5 MHz at 10-Mbps operation and 25 MHz at 100-Mbps operation. |
MIITXER | O | This pin is always driven low from the MAC controller on the device. |
MIITXD[3-0] | O | Transmit data. The transmit data pins are a collection of four data signals comprising 4 bits of data. MTDX0 is the least-significant bit (LSB). The signals are synchronized by MIITXCLK and are valid only when MIITXEN is asserted. |
MIITXEN | O | Transmit enable. The transmit enable signal indicates that the MIITXD pins are generating nibble data for use by the PHY. MIITXEN is driven synchronously to MIITXCLK. |
MIICOL | I | Collision detected. In half-duplex operation, the MIICOL pin is asserted by the PHY when the PHY detects a collision on the network. The MIICOL pin remains asserted while the collision condition persists. This signal is not necessarily synchronous to MIITXCLK or MIIRXCLK. In full-duplex operation, the MIICOL pin is used for hardware transmit flow control. Asserting the MIICOL pin will stop packet transmissions; packets in the process of being transmitted when MIICOL is asserted will complete transmission. The MIICOL pin should be held low if hardware transmit flow control is not used. |
MIICRS | I | Carrier sense. In half-duplex operation, the MIICRS pin is asserted by the PHY when the network is not idle in either transmit or receive. The pin is deasserted when both transmit and receive are idle. This signal is not necessarily synchronous to MIITXCLK or MIIRXCLK. In full-duplex operation, the MIICRS pin should be held low. |
MIIRXCK | I | Receive clock. The receive clock is a continuous clock that provides the timing reference for receive operations. The MIIRXD, MIIRXDV, and MIIRXER signals are tied to this clock. The clock is generated by the PHY and is 2.5 MHz at 10-Mbps operation and 25 MHz at 100-Mbps operation. |
MIIRXD[3-0] | I | Receive data. The receive data pins are a collection of four data signals comprising 4 bits of data. MRDX0 is the least-significant bit. The signals are synchronized by MIIRXCLK and are valid only when MIIRXDV is asserted. |
MIIRXDV | I | Receive data valid. The receive data valid signal indicates that the MIIRXD pins are generating nibble data for use by the EMAC. MIIRXDV is driven synchronously to MIIRXCLK. |
MIIRXER | I | Receive error. The receive error signal is asserted for one or more MIIRXCLK periods to indicate that an error was detected in the received frame. The MIIRXER signal being asserted is meaningful only during data reception when MIIRXDV is active. |
MDIO_CK | O | Management data clock. The MDIO data clock is sourced by the MDIO module on the system. MDIO_CK is used to synchronize MDIO data access operations done on the MDIO pin. The frequency of this clock is controlled by the CLKDIV bits in the MDIO Control Register (CONTROL). |
MDIO_D | I/O | Management data input output. The MDIO data pin drives PHY management data into and out of the PHY by way of an access frame that consists of start-of-frame, read/write indication, PHY address, register address, and data bit cycles. The MDIO_D pin acts as an output for all but the data bit cycles, at which time the pin is an input for read operations. |