RM0319 datasheet(153/368 Pages) STMICROELECTRONICS

153 / 368 page

RM0319

Fast Ethernet port (MII0)

Doc ID 022640 Rev 3

153/368

The signal pmt_intr_o reflects the combination of the value PMT_INTR in the MAC interrupt

status register (Interrupt Status Register (Register14, MAC), bit 3) and the value

PMT_INTR_MASK in the MAC interrupt mask register (Interrupt Mask Register (Register

15,MAC), bit 3).

Interrupts can be generated from the MAC Core as a result of various events in the optional

modules in it (for example MMC and PMT modules). These interrupt events are combined

with events in the DMA on the sbd_intr_o signal. Infact the signal pmt_intr_o is also used to

drive the signal sbd_intr_o (GPI in the figure above).

In the same way the MMC block through MMC_INTR (controlled by Interrupt Status Register

(Register14, MAC), bit 4) drives the sbd_intr_o signal (GMI in the figure above).

The other events in the DMA that drive the sbd_intr_o signal are produced by the

combinations of status register bits and interrupt mask bits (listed correspondingly in the

Status Register (Register5, DMA) and Interrupt Enable Register (Register7, DMA)).

12.6

Programming examples

How to initialize DMA

Write to DMA register0 (Bus Mode) to set the host bus access parameters.

Write to DMA register7 (Interrupt Enable) to mask needless interrupt causes.

Create the Transmit And Receive descriptor lists into the host physical memory space.

Write to both DMA register3 (Receive Descriptor List Address) and register4 (Transmit

Descriptor List Address) providing the DMA with the starting address of each descriptor

list.

Write to MAC register1 (MAC Frame Filter), register2 (Hash Table High) and register3

(Hash Table Low) for described filtering options.

Write to MAC register0 (MAC configuration) to configure and enable the Transmit And

Receive operating modes. The PS and DM bits are set based on the auto-negotiation

result (read from the PHY).

Write to DMA register6 () setting bits [1] SR and [13] ST to start reception and

transmission, respectively.

RM0319 датащи(PDF) 153 Page - STMicroelectronics