Talking about the instructions of the remote control module. Detailed explanation of the function of the power window remote control module

The module must use signal modulation to work normally. Common fixed code encoding devices such as PT2262/2272 can be directly connected, which is very simple. Because it is a dedicated encoding chip, the effect is very good and the transmission distance is very long. Another important use of the module is to cooperate with the microcontroller to achieve data communication. At this time, there are certain skills:

1. Reasonable communication rate

The maximum transmission data rate of the data module is 9.6KBs, which is generally controlled at about 2.5k. Excessive data rate will reduce the receiving sensitivity and increase the bit error rate or even fail to work at all.

2. Reasonable information code format

When the single-chip microcomputer and the module work, they usually define the transmission protocol by themselves. No matter what modulation method is used, the information code format to be transmitted is very important, and it will directly affect the reliable transmission and reception of data.

Recommended code group format

Preamble + synchronization code + data frame, the length of the preamble should be greater than 10ms to avoid background noise, because the first bit of the data received by the receiving module is easily interfered (ie zero-level interference) and causes the received data error. Therefore, the use of CPU encoding and decoding can add some garbled codes before the data identification bit to suppress zero-level interference. The synchronization code is mainly used to distinguish it from the preamble and data. There are certain characteristics, so that the software can identify the synchronization code through a certain algorithm, and prepare for receiving data at the same time.
It is not advisable to use non-return-to-zero codes for data frames, let alone length 0 and length 1. Use Manchester code or POCSAG code, etc.

3. The interference of the single-chip microcomputer to the receiving module

When the single-chip microcomputer simulates 2262, it is generally normal. However, when the single-chip microcomputer simulates 2272 decoding, it is usually found that the remote control distance is shortened a lot. This is because the multiplication of the clock frequency of the single-chip microcomputer will cause interference to the receiving module. The electromagnetic interference of the 51 series single-chip microcomputer is relatively large, 2051 Slightly smaller, the PIC series is relatively small, we need to adopt some anti-interference measures to reduce interference. For example, the single-chip microcomputer and the remote control receiving circuit are powered by two 5 volt power supplies, and the receiving board is powered by a 78L05 separately. The clock area of ​​the single-chip microcomputer is far away from the receiving module, the operating frequency of the single-chip microcomputer is reduced, and the shielding is added in between.
It is better to make an isolation circuit when the receiving module and the 51 series single-chip microcomputer interface, which can better contain the electromagnetic interference of the single-chip microcomputer to the receiving module.

Generally, the output of the receiving module is high-level pulse, not DC level, so it cannot be tested with a multimeter. When debugging, a light-emitting diode can be connected in series with a 3K resistor to monitor the output status of the module.
When the wireless data module is used with dedicated codec chips such as PT2262/PT2272, the connection is very simple. Just connect directly. The transmission distance is ideal, generally up to 600 meters or more. If it is used with a single chip microcomputer or a microcomputer, it will be affected by the single chip microcomputer or microcomputer. The clock interference caused the transmission distance to be significantly reduced, and the general practical distance is within 200 meters.

The remote control module is one of the modules of the smart window control system (the module cannot be used alone). The remote control module controls the window module and switch module in the smart window system by receiving the control signal transmitted by the remote control, so that the user can quickly and easily realize the specified The window unit performs actions such as opening, closing, and stopping;

Area A: The 9 groups of button settings on the interface correspond to the button operation units 1-9 on the remote control. Each group of buttons can control 4 groups of window units, and the unit number range is (1~254);

Area B: The device serial port is set to the port number of the module access mapping;

Area C: local identification code, set to the same number in the same control group;

Area D: write parameters: write parameters to the module;

Read parameters: read the parameters from the module;

Recall settings: recall the pre-saved parameters;

Save settings: save existing parameters;