1 Product Description
1.1 Modules Introduction
UTC-4432 is a low-cost sub-1 GHz transceiver module designed for operations in the unlicensed ISM (Industrial Scientific Medical) and LPRD bands. GFSK (Frequency Shift Keying) modulation/demodulation, multi-channel operation, high bandwidth efficiency and anti-blocking performance make UTC-4432 modules easy to realize the robust and reliable wireless link.
The module can be configured to work in different channels with 200kHz space. It adopts high efficient looped interleaving EDAC (Error Detection and correction) coding with coding gain up to 3dB which keeps in advance in EDAC and coding efficiency over normal FEC (Forward Error Correction). Because of its high reliability in correction, modules can filter error and fake information automatically and realize truly transparent wireless link, which makes EUTC-4432 very suitable in the rigid communication environment.
UTC-4432 integrates 256 bytes buffer. When the buffer is empty, users can transfer 256 bytes data per time and even limitless data transfer can be achieved as long as RF data rate (RF module to RF module) is configured to be faster than UART data rate (MCU to RF module). The module provides standard UART/TTL interface for selection. Users can choose seven data rates and three parity checks which make UTC-4432 possibly tailor-made for different applications. UTC-4432 operates at 3~3.6V with extra low standby current which makes it suitable for battery powered-up applications.
For different applications, UTC-4432 modules have different types:UTC-4432B1 without the shield and UTC-4432B1M which equipped with metal shielding. Both interfaces are identical and compatible with each other; Both the appearance and dimensions of different, respectively, as shown in the following figure:
UTC-4432B1 (34.72 x 19.96 x 7mm)
UTC-4432B1M (39.96 x 24.96 x 7mm)
UTC-4432B1M as a upgraded version of UTC-4432B1, stronger anti-interference performance, recommended used in applications environment with larger interference.For example:near the substation, places where have strong electromagnetic wave, wireless applications of power.
1.2 Functional Properties
1.2.1 Highlight Features
l Support wireless wake-up function, Average power consumption of the modules in wireless wake-up mode are 2uA-20uA（according to the parameters to set it）.
l While maintaining low power consumption, with high sensitivity and long distance as far as transfers above 2000m.
l Support to modify RF and functional properties of the modules online ( user modified them by MCU ) and locally ( use assorted PC-side of Hangzhou Fytoo Technologies to configure software ), use more convenient and easier networking.
l Support online listening RF air channel, physical layer support wireless anti-collision protocol;Using wireless anti-collision and hardware physical mechanism, effectively solving the co-channel interference problems of the surrounding systems, this could be a reliable communication, further reduces power consumption and extend the life of the node.
l Bulk data buffers, supports a maximum of 256-byte length data packets at a time.
l FEC forward error correction mechanism, use the method of transmission of redundant information, when an error occurs in the transmission, allows the receiver to build data, greatly improving wireless communication anti-jamming capability.
Anti-collision mechanism description: Usually the terminal code is in power saving mode (mode 3), base station is in wake-up mode (mode 2), base station send wake data packet which contains specified terminal node hardware address, after corresponding node is wake, can switch it to normal transceiver data mode (mode 1) by user MCU. Terminal node listens to the air RF channel to make sure whether there is carrier (need to open carrier sense) before send data. If there is carrier, delay a random time and listen to air carrier again until there isn't carrier, and then send data to the base station, without affecting the other hardware address corresponding node.
1.3 Basic characteristics
l Supply voltage 3~3.6V
l UART interface（TTL level）
l Visual transmission distance 2000m（air rate 1kbps）
l FSK modulation, Efficient error correction coding, Strong anti-interference ability
l RF parameters such as frequency, air speed, the transmission power configurable
l Serial port parameters such as baud rate and parity type configurable
l Local IP address and destination address could be modified, support multiple points star network
l Packet length configurable
l Support package complete transmission mode
l Wake-up interval, delay trigger time configurable
l -40℃~+85℃
l 34.72 x 19.96 x 7.0mm（UTC-4432B1），39.96 x 24.96 x 7.0mm（UTC-4432B1M）
l Standard 2.54mm DIP spacing
Package size, interface level, power supply, etc., and other outstanding features, can be customized as appropriate.
1.4 Application
While maintaining low power consumption, the UTC-4432 module greatly improves its receiver sensitivity and transmission distance. When its air transmission rate is 1kbps, receiver sensitivity to -121dBm, transmission distance up to 2000m. Particularly suitable for long distance, penetrating ability, strong anti-interference, low power consumption in the demanding environment.
EUTC-4432 modules are widely used in following industries:
l Automatic meter reading
l Wireless sensor network
l Home automation
l Security alarm
l Intelligent instrument
l Intelligent lighting control
l POS systems, asset management
l Wireless weighing
l Wireless storage, logistics management
l Automated data acquisition
l Industrial remote control, telemetry, remote sensing and mapping
l Highways, railway data transmission
l Heat supply network, gas network, water supply monitoring and automation
l Electric power distribution monitoring, power load monitoring
l Contact less access
l Wireless data logger
2 PIN Information
UTC-4432 series module has 7 pins, described as follows:
2.1 PIN Assignment Chart
2.2 PIN Functions
PIN / Name / Function / Description1 / GND / Ground / Ground(0V)
2 / VCC / Power / Power supply(3V-3.6V)
3 / SET_A / Input / Used to select the module working model
4 / RXD / Output / UART input, TTL level
5 / TXD / Output / UART output, TTL level
6 / AUX / Output / Used to indicate the module working condition
7 / SET_B / Input / Used to select the module working model
When module connects with user MCU, SET_A and SET_B pins respectively connect to the two GPIO ports of MCU, RXD and TXD two pins of the module connect to TX and RX two pins of the MCU serial port, AUX pin connects to the external interrupt pin of MCU ( AUX not required, if not using, maintain vacant). Connection diagram is as follows:
3 Technical Specifications
3.1 Working Mode
UTC-4432, a total of 4 working modes, use SET_A and SET_B two pins to set, 4 modes are interchangeable.
Working Mode / PIN Configuration / DescriptionNormal mode
(mode 1) / SET_A=0
SET_B=0 / Serial UART opened, module continued in receiving state. When UART is written data to be sent, set AUX low and switch to sending state, and send the data. After the end of data sent, reset AUX pin high and turn to continued receiving state.
Module sends data in this mode, without sending a long preamble, so requires the receiver must in mode 1 or mode 2, which is continued receiving state.
The module, after receiving data from the air RF channel, when through CRC check and confirm that the data is correct, set AUX low and immediately output data from the serial port. Set AUX high after the end of the data output.
Wake-up mode
(mode 2: active wake) / SET_A=0
SET_B=1 / Serial UART opened, module continued in receiving state. When UART is written data to be sent, set AUX low and switch to sending state, and send the data. Send a special wake packet whose preamble length is a wake-up cycle (such as 1s), and after the end of data sent, reset AUX pin high and turn to continued receiving state.
Module sends data in this mode, because the data sent has a long preamble, the receiver can receive the data in mode 1, mode 2, or mode 3.
The module, after receiving data from current channel, when through CRC check and confirm that the data is correct, set AUX low and immediately output data from the serial port. Reset AUX high after the end of the data output.
Power saving mode
(mode 3: passive wake ) / SET_A=1
SET_B=0 / Serial UART closed. A wake-up cycle (such as 1s) later, RF receiver opened and search channel for preamble. If not found, then immediately goes into dormancy state, waiting for the next wake-up cycle to wake up again. If monitored a preamble,continued to stay in receiving state to wait for the synchronization code and receives it. When through CRC check and confirm that the data is correct, set AUX low to wake the lower computer, then open the serial port and output data.
After the end of serial output, close the serial port and reset AUX high. If the mode setting isn't changed, goes into dormancy state to wait for the next wake-up cycle.
Sleep mode
(mode 4: configuration mode) / SET_A=1
SET_B=1 / In this state, the RF circuit of module, CPU clock and peripherals will be closed, power consumption of about 1.5 uA. This mode is primarily used to configure their parameter settings and close the module when it doesn't need to send and receive data. When you configure the module parameters, UTC module serial port fixed to 9600bps, 8 data bits, 1 stop bit and no parity. Switch to the other 3 modules for users to set values.
When the module works in mode 2, can send and receive wireless data.. In mode 3, can receive wireless data, but couldn't send data, and if need to send data, it should be switched to mode 1. When the sending terminal works in mode 1, the receiving terminal must work in mode 1 or mode 2.
3.2 Normal Communication
When the module in normal mode (mode 1), two-way communication between modules. At the same time, modules listening to the serial port and air RF channel. So the modules can be used as both transmitter and receiver.
l The process of sender and receiver as follows:
Ø Sending terminal processing（SET_A PIN low，SET_B PIN low）
When listening to the serial port data input, set AUX pin low and switch to wireless transmitter state, interwoven error correction coding of the data received on the serial port, and then sent over the RF channels. Reset AUX pin high and again transferred to continuously listening state after the end of transmission.
Ø Receiving terminal processing（SET_A PIN low，SET_B PIN low）
After receiving data from the air RF channel, through interwoven error correction decoding and error detection to confirm that the data received is correct, set AUX pin low and immediately output the decoded data from the serial port. Reset AUX pin high and again transferred to continuously listening state after the end of transmission.
l Description the process of the two modules in detail ,when they are working in normal mode, as follows:
1. Through external MCU GPIO ports configure SET_A and SET_B two pins as a low level so that both modules are in the normal state (mode 1). Or SET_A and SET_B pins of each module could be connected to the GND directly (can reduce take up MCU 2 IO ports).
This status mode, the module allows for half-duplex communications, both as a sender and a receiver. RF parameters of sending and receiving terminal of the module must be configured the same, it could communicate when the transceiver destination address match.
2. When the sender module listens to serial data input, set AUX pin low and automatically switch to wireless transmitter state, and then send serial data over the air RF channel that you just received. Reset AUX pin high and again transferred to continuously listening after the end of transmission, always ready to receive other data information.
3. Receiver module listens to the air carrier, receive data given by the transmitter module from air RF channel. After CRC check and confirm the received data is correct, set AUX pin low and immediately output the decoded data from the serial port. After all the data from the UART output, reset AUX pin high and again transferred to continuously listening state.
If the receiving module needs to send data, only need external MCU transmit data to others through UART interface and the module will transmit automatically.
Module workflow described as follows:
3.3 Low-power Communication
When the module is in low-power receiving mode, the receiving module through the timing of sleep and listens to air RF channels to achieve the purpose of low power. And the transmitter module communicates with the receiver module by sending a special RF packet.
l The process of sender and receiver as follows:
Ø Sending terminal : SET_A PIN low level，SET_B PIN high level
When listening to the serial port data input, set AUX pin low and switch to wireless transmitter state, interwoven error correction coding of the data received on the serial port, and build a special data packet whose preamble length is a wakeup period, then sent over the RF channels. Reset AUX pin high and again transferred to continuously listening state after the end of transmission.
Ø Receiving terminal : SET_A PIN high level, SET_B PIN low level
After initializing the RF part of the module, it goes into the state of dormancy. After a wake-up period (such as 1 second), the RF part in the receiving state and searching for the air RF channels whether there is a preamble. If there is no search, then immediately goes into the state of dormancy to wait for the next wake-up period and then search again. If found, continue to keep in the receiving state, receive the remaining portion of the data packet. And then through interwoven error correction decoding and error detection to confirm that the data is correct, set AUX pin low and output the decoded data from the serial port after waiting for a delay trigger time. Reset AUX pin high after the end of transmission.If the working status does not change, goes into the state of dormancy again to wait for the next wake-up period.
If the receiving terminal need to return data to the sending terminal, by changing the working state of the receiving terminal, set SET_A pin and SET_B pin to low levels. Communicating by the way of normal communication mode at this time.
l Low-power communication diagram as shown in the following figure: