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 33
Ω
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)
