User's Manual

Boomer-III User Manual & Integrator’s Guide_________________________________________________Installation
BM310012WT05 31 Copyright Wavenet Technology © October 2003
Serial Communications Interface
The modem communicates with the controller using the Data Interface
Port connection interface. The host asynchronous serial interface on the
Boomer-III OEM Modem operates at 3V and can be controlled by a
wide variety of micro controllers and microprocessors.
If the modem is to be connected directly to a PC or other RS232
device, an interface must be provided to convert the signal voltage to
the higher values required by an RS232 device.
The protocol supported over this link is network dependant. The data
format is generally: 8 data bits, no parity, 1 stop bit, unless otherwise
specified.
The serial interface lines (RXD, TXD, DCD, DTR, DSR, RTS, CTS,
RI) are 3V logic compatible. They are fitted with a 33Ω series resistor
for protection. The electrical interface capability, equivalent circuit and
operation of these lines is summarized below:
Serial Communications Interface Definitions
J1
Pin #
Signal Description Signal Active State
1
DCD
Data Carrier Detect
Output Low when modem in-range
2
RXD
Receive Data
Output Low when active
3
TXD
Transmit Data
Input Low when active
4
DTR
Data Terminal Ready
Input Low when ready
6
DSR
Data set ready
Output Low when ready
7
RTS
Request to send
Input High when host/terminal
requires data throttling
8
CTS
Clear to send
Output High when modem requires
data throttling
9
RI
Ring indicator
Output Pulses Low when messages
are waiting