User's Manual

Boomer-III User Manual & Integrator’s Guide_________________________________________________Installation
BM310012WT04 37 Copyright Wavenet Technology © October 2003
LED Output Lines
In addition to the on-board LED’s there are three signal lines (Low
Battery, Message Waiting, In-range), which are controllable by the
modem for connection to an external LED. These lines also have multi-
function capability through software configuration as digital
input/outputs or as a Synchronous Peripheral Interface (SPI) port. SS4
may be used as a SPI chip select signal (refer to Status Signals section
previously).
Each LED output line has a 33Ω series resistor for protection. It is
recommended a series resistor be used with the external LED to limit
current accordingly. The electrical interface capability, equivalent
circuit and operation of these lines is summarized in the tables below:
LED Output Interface Definitions
J1
Pin #
Signal Description
Digital
Capability
Alternate
Function
13 LED0_MSGWTG LED Signal 0 Input/ Output SPI_CLK
14 LED1_INRANGE LED Signal 1 Input/ Output SPI_MOSI
15 LED2_LOWBAT LED Signal 2 Input/ Output SPI_MISO
LED Output Lines Equivalent Circuit
LED Interface Electrical Characteristics
Parameter Range Low High
Output Voltage 0 – 3V 0.4 V (max) 2.5 V (min)
Output Current 4 mA (max) 4 mA (min)