AMD Am79C930 - page 122

AMD P R E L I M I N A R Y

122 Am79C930

is set to a 0, the Baud Detect Count for Stop Diversity is not used in

the stop diversity decision logic.

1 UBDCS 0 Use Baud Detect of Carrier Sense in CCA decision. When this bit is

set to a 1, the Baud Detect Count for Carrier Sense becomes one

input to the clear channel assessment logic. When this bit is set to a

0, the Baud Detect Count for Carrier Sense is not used in the clear

channel assessment decision.

0 URSSI 0 Use RSSI in CCA and Stop Diversity decisions. When this bit is set

to a 1, the RSSI converted value comparison to the RSSI lower limit

becomes one input to the clear channel assessment logic and also

becomes one input to the Stop Diversity decision logic. When this

bit is set to a 0, the RSSI converted value comparison to the RSSI

lower limit is not used in the clear channel assessment logic and is

also not used in the Stop Diversity decision logic.

TCR29: Reserved

This register is a TAI reserved location.

CONFIGURATION REGISTER INDEX: 1Dh

Bit Name Reset Value Description

7–0 Reserved – Reserved. Must be written as a 0. Reads of this bit produce

undefined data.

TCR30: Pin Function and Data Rate

This register is the Pin Function and Data Rate control

pins as well as control bits to set the network data rate.

CONFIGURATION REGISTER INDEX: 1Eh

Bit Name Reset Value Description

7 ANTSLTLFN 0 ANTSLT Function. ANTSLTLFN, ANTSLTLEN (TCR15[7]),

ANTSEN (TIR26[3]), and the PCMCIA pin are used to determine

the direction and data of the ANTSLT pin.

The control of the function of the ANTSLT/LA23 pin is described in

the

Multi-Function Pin

section.

6 TXDLFN 0 TXDATA Function. TXDLFN, TXDLEN (TCR15[6]), and the

PCMCIA pin are used to determine the direction and data of the

TXDATA pin.

The control of the function of the TXDATA/LA23 pin is described in

the

Multi-Function Pin

section.

5 TXCMFN 0 TXCMD Function. TXCMFN, TXCMEN (TCR15[5]), RCEN

(TIR11[3]), and the PCMCIA pin are used to determine the function

of the TXCMD pin.

4 USER7FN – Reserved. Must be written as 0. Reads of this produce

undefined data.

The control of the function of the TXCMD/LA21 pin is described in

the

Multi-Function Pin

section.

3 TXCIN 1 TXC Input. When set to a 0, the TXC pin functions as an output, pro-

viding a divide by X version of the CLKIN input, where X is deter-

mined by the setting of the DR bits of TCR30. When set to a 1, the

TXC pin functions as an input, allowing the data rate of the transmit

operations to be set by an external source. When TXCIN is set to 1,