User's Manual

30 68P80801E35-A 9/1/2001

Troubleshooting EBTS System Manual - Vol 2

Generation 2/EBRC Single Channel Base Radio Backplane

Backplane Signals

Table 3 provides a list of all signals routed on the backplane interconnect board.

Table 3 BR Backplane Signal Descriptions

Signal Description

GND Station Ground

28.6 V 28.6 VDC Output from PS

14.2 V 14.2 VDC Output from PS

5.1 V 5.1 VDC Output from PS

A0, A1, A2, A3, A4, A5, A6** The BRC uses these lines to address station modules and devices on those modules

SPI_MOSI Serial Processor Interface- Master out, slave in Data

SPI_MISO Serial Processor Interface- Master in, slave out Data

SPI_CLK Serial Processor Interface- Clock Signal (100 KHz- 1MHz)

ACG1, ACG2, ACG3, ACG4 BRC uses these lines to set digital attenuators on the receiver(s) for SGC functionality

2.1MHZ_RX 2.1 MHz generated on the BRC and used as a reference by the Receiver(s)

2.1MHZ_TX 2.1 MHz generated on the BRC and used as a reference by the Exciter

DATA1, DATA1* This differential pair carries Receiver 1 data to the Base Radio Controller

DATA2, DATA2* This differential pair carries Receiver 2 data to the Base Radio Controller

DATA3, DATA3* This differential pair carries Receiver 3 data to the Base Radio Controller

ODC_1, ODC_2, ODC_3 Clocks used to clock differentiual receive data from each respective receiver to the BRC

SBI_1,S BI_2, SBI_3 Serial Bus Interface - these lines are used to program the custom receiver IC oin each

receiver

SSI, SSI* Differentiual transmit data from the Exciter to the BRC

CLK, CLK* Differential Data clock used to clock transmit data from the BRC to the Exciter

VBLIN Programmable bias voltage generated on the Exciter and used to bias PA stages

RESET* Output from BRC to Exciter

EXT_VFWD DC voltage representing the forward power at the antenna as measured by the external

watt meter

EXT_VREF DC voltage representing the reﬂected power at the antenna as measured by the external

watt meter.

WP* Write protect line used by the BRC to write serial EPROMs located on each module

BAT_STAT Binary ﬂag used to signal BRC to monitor the External battery supply alam

METER_STAT Binary Flag used by the BRC to indicate to the BRC it should monitor

PA_ENABLE* The BRC uses this line to control PA bias.

1PPS Global Positioning System- 1 pulse per second (this may be combined with 5 MHz at the

site frequency reference)