TNETA1585

ATM TRAFFIC MANAGEMENT SCHEDULER DEVICE

WITH RECEIVE UTOPIA AND COPROCESSOR INTERFACES

SDNS041A – NOVEMBER 1996 – REVISED JULY 1998

13

POST OFFICE BOX 655303

transmitted-cell-indication interface (TCCX) (continued)

Bit 1 (send acknowledge). This bit indicates whether the SAR will send a cell. The bit is encoded as follows:

BIT 1

INDICATION

0

Cell will not be sent.

1

Cell will be sent.

Bit 0 (framing). This bit is set to a 1 to denote the start of a frame.

The frame is transmitted to the coprocessor through the TCCX terminal starting with bit 0. When a frame is not

actively being transmitted, the TCCX terminal is driven to a 0.

data-availability interface (DAX)

A single-bit interface allows the TNETA1575 to signal to the TNETA1585 when data is available or unavailable

on a particular channel. A 13-bit frame is sent to the TNETA1585 for a particular channel only when its

data-availability status changes (i.e., when the host writes to the transmit-queue register to notify the

TNETA1575 that a packet has been queued, or if the TNETA1575 completes segmentation of the last packet

on a particular channel). The frame is formatted as follows:

Channel number (12–2)

Data available/unavailable (1)

Framing (0)

Bits 12–2 (channel number). These bits indicate which one of the 2K channels has available or unavailable data.

Bit 1 (data available/unavailable). This field indicates the new status of the segmentation queue for the given

channel number. This field is encoded as follows:

BIT 1

INDICATION

0

All data has been segmented (data unavailable).

1

New data has been added (data available).

Bit 0 (framing). This bit is set to a 1 to denote the start of a frame.

The frame is transmitted to the TNETA1585 through the DAX terminal starting with bit 0. When a frame is not

actively being transmitted, the DAX terminal is driven to a 0.

COP full-indication interface (COPFULL)

A single-bit interface allows the TNETA1585 to signal to the TNETA1575 the status of the TNETA1585’s

receive-UTOPIA-interface FIFO. When in ATM mode (CONFIG = 0), this output goes high when the

receive-UTOPIA-interface FIFO is full. When in PHY mode (CONFIG = 1), this output goes high when the FIFO

is within four bytes of being full.