AM79C930 datasheet(31/161 Pages) AMD

31 / 161 page

P R E L I M I N A R Y

AMD

Am79C930

TXMOD

Transmit Modulation Enable

Output

TXMOD is an active low output that is used to enable the

transmit modulation function of the attached trans-

ceiver. This pin is directly controlled by the transmit state

machine in the TAI and the

TXMOD bit of TIR11. The

timing of the

TXMOD signal is programmable from a TAI

TAI register.

TXPE

Transmit Power Enable

Output

TXPE is an active low output that is used to enable the

transceiver’s transmission amplifier. When

TXPE is low,

the transceiver should enable its transmission amplifier.

When

TXPE is high, the transceiver should disable its

transmission amplifier. This pin is directly controlled by

the transmit state machine in the TAI and the

TXPE bit of

the TIR11. The timing of the TXMOD signal is program-

mable from a TAI register. The polarity of this pin is pro-

grammable from a TAI register.

USER7

Input/Output

USER7 is a pin that may be directly controlled through

TIR and TCR register locations.

Other Pins

ACT

Activity LED

Output

ACT is an active low open collector output that is directly

controllable through a TAI register. This pin is capable of

sinking the 12 mA necessary to drive a typical indicator

LED. This pin is directly controllable through a TAI regis-

ter and is also programmable as an I/O with read capa-

bility. This pin may also be programmed to actively drive

high output values. When an LED is connected to this

pin, then proper operation of this output requires a

pull-up device to be connected externally.

ADREF

A/D Reference

Input

ADREF is a single-ended analog input that is used by

the A/D conversion circuit. ADREF is the reference volt-

age that is fed to the resistor ladder of the D/A portion of

the A/D circuit. ADREF is used to determine the range of

sensitivity of the A/D circuit. The recommended value

for ADREF is 1.25 to 1.75 V. Note that ADREF is volt-

age-doubled before being used for internal A/D refer-

ence. For example, an ADREF value of 1.75 V will mean

that the A/D will give a max digital output value for an

ADIN input of 3.5 V or higher.

ADIN[1–2]

A/D sample inputs

Input/Output

ADIN[1–2] are inputs that accept single-ended analog

input values for conversion by the internal Am79C930

A/D converter. Only one input will be sampled at any

time for conversion by the internal Am79C930 device’s

A/D circuit. The input that will be converted by the

A/D circuit is determined by the setting of the SRCS bit

of the Antenna Diversity and A/D Control register in the

TAI (TIR26).

LNK

Link LED

Output

LNK is an active low open collector output that is directly

controllable through a TAI register. This pin is capable of

sinking the 12 mA necessary to drive a typical indicator

LED. This pin is directly controllable through a TAI regis-

ter and is also programmable as an I/O with read capa-

bility. This pin may also be programmed to actively drive

high output values. When an LED is connected to this

pin, then proper operation of this output requires a

pull-up device to be connected externally.

PWRDWN

Powerdown

Output

PWRDWN is an output that becomes active (HIGH)

when the Am79C930 device enters the power down

mode. This pin can be used to power down other sec-

tions of a Am79C930-based system design.

SAR[6–0]

Serial Approximation Register

Input/Output

SAR[6–0] are outputs that are used to deliver the value

of the internal A/D converter for use external to the

Am79C930 device. These pins are directly controllable

through a TAI register and are also programmable as

I/O pins with read capability.

SDCLK

Serial Device Clock

Output

SDCLK is an output that is used to clock data on the

SDDATA output pin. This pin may be used in combina-

tion with the SDDATA and

SDSEL output pins in order to

create an I2C serial device interface. This pin is directly

controllable through a TAI register and is also program-

mable as an I/O with read capability.

SDDATA

Serial Device Data

Input/Output

SDDATA is an I/O pin that may be used in conjunction

with the SDCLK and

SDSEL pins in order to create an

I2C serial device interface. This pin is directly controlla-

ble through a TAI register and is also programmable as

an I/O with read capability.

SDSEL[1–3]

Serial Device Select

Output

SDSEL[1–3] are output pins that may be used in con-

junction with the SDCLK and

SDSEL pins in order to cre-

ate an I2C serial device interface. These pins are directly

controllable through a TAI register and are also pro-

grammable as I/O pins with read capability.

AM79C930 Datasheet(PDF) 31 Page - Advanced Micro Devices

AM79C930 Datasheet(HTML) 31 Page - Advanced Micro Devices

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

Datasheet Download

Link URL