STLC5466 datasheet(73/130 Pages) STMICROELECTRONICS

73 / 130 page

73/130

STLC5466

VII.2.3 - Receive Buffer

Each receive buffer is defined by its receive descriptor.

The maximum size of the buffer is 2048 words (1 word=2 bytes)

VII.3 - Transmit Descriptor

This transmit descriptor is located in shared memory. The quantity of descriptors is limited by the memory

size only.

The 5 first words located in shared memory to TDA+00 from TDA+08 are written by the microprocessor

and read by the DMAC only. The 6th word located in shared memory in TDA+10 is written by the DMAC

only during the frame reception and read by the microprocessor.

VII.3.1 - Bits written by the Microprocessor only

ABORT. The received frame has been aborted by the remote transmitter or the

local microprocessor.

OVERFLOW of FIFO. The received frame has been aborted.

The received frame had not an integer of bytes.

RBA

First Buffer Location

RBA + SOB-2

Last Location Available = Receive Buffer Address (RBA) + Size Of the Buffer (SOB-2)

TDA+00

BINT

BOF

EOF

EOQ

Number of Bytes to be Transmitted (NBT)

TDA+02

Not used

CRCC

PRI

TBA High (8 bits)

TDA+04

Transmit Buffer Address Low (16 bits)

TDA+06

Not used

NTBA High (8 bits)

TDA+08

Next Transmit Descriptor Address Low (16 bits)

TDA+10

CFT

ABT

UND

NBT

: Number of Bytes to be transmitted (up to 4096).

TBA

: Transmit Buffer Address. LSB of TBA Low is at Zero mandatory.

TDA

: Transmit Descriptor Address.

NTDA : Next Transmit Descriptor Address. LSB of NTDA Low is at Zero mandatory.

BINT

: Interrupt at the end of the frame or when the buffer is become empty.

BINT = 1,

if EOF = 1 the DMAC generates an interrupt when the frame has been transmitted;

if EOF = 0 the DMAC generates an interrupt when the buffer is become empty.

BINT = 0, the DMAC does not generate an interrupt during the transmission of the frame.

ABT

OVF

FCRC

Definition

STLC5466 Arkusz danych(PDF) 73 Page - STMicroelectronics

STLC5466 Arkusz danych(HTML) 73 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Arkusz danych Pobierz

Link URL