Rainbow Electronics RC1290 - Manual (Page 2)

RC1240/1280/1290
 2005 Radiocrafts AS RC1240/RC1280/RC1290 Data Sheet (rev. 1.3) Page 2 of 17
Typical Application Circuit
GND
CTS/RXTX/RXEN
RTS/TXEN
CONFIG
TXD/SCL
RXD/SDA
GND
GND
VCC
ON/OFF
VDD
GND
RF
GND
2.8 - 5.5 V
Antenna
{
To host MCU or
RS232/422/485
driver
NC
Quick Product Introduction
How do I transmit data?
Send your data to the RXD pin on the module. Use the UART format with settings (19200, 8,
1, N, no flow control). Up to 128 bytes are buffered in the module. The module will transmit
the data when
• the max packet length is reached
• the unique end character is sent
• the modem timeout limit is reached
The packet length, end character and timeout limit are configurable in-circuit.
How do I receive data?
Any received data packet with correct address and check sum will be sent on the TXD pin
using the same UART format as for transmit.
What about the antenna?
In most cases a simple quarter wavelength wire or a PCB track will do. Connect a piece of
wire to the RF pin with length corresponding to the quarter of a wavelength. For space limited
products, contact Radiocrafts and we will recommend the best antenna solution for your
application.
How do I change the RF channel or any other parameter?
To change configurable parameters, assert the CONFIG pin, and send the command string
using the same serial interface as for transmitting data. Parameters can be changed
permanently and stored in non-volatile memory in the module.