Initial version ATDR reply distinguishing module ATSE, ATGE add audio switch Add ATSP protocol Add ATST, ATGT protocol ATGE command add AESfor status acquisition Added ATGB protocol AV and HDMI output control Support for obtaining the current AV output standard Added ATSU, ATGUcommands Added ATOSD, ATSIP, ATGIP commands Added ATSAD, ATGAD commands
Users may need to modify the configuration parameters of the module during the use of the COFDM modulator and demodulator module. In order to simplify the user’s operation, we design the parameter configuration into a few simple AT commands. The user only needs to use the specified AT command and pass the corresponding parameters to complete the parameter setting of the COFDM module.
The AT command for configuring COFDM module parameters starts with “AT” and ends with an underscore “_”. Each AT command has several or no parameters, and each AT command has a return value. For details, please refer to the introduction of the following commands.
Users can configure the parameters of the module through the configuration serial port (TTL level, 3.3V) of the COFDM module. For detailed serial port configuration, refer to the figure below. Please use tools such as “Serial Port Debugging Assistant” to send AT commands to the COFDM module, pay attention to the use of text, for example:
Encoder Modulator Decoder Demodulator Module
Command Classification
The AT commands for configuring COFDM module parameters are mainly divided into the following two categories:
such as:ATSD0,1,0,0,800000,8000,86.0,86.0_ SISO,GI: 1/16, CR:1/2, MOD: QPSK, freq:800000KHz,bw:8000KHz,tx1_gain:86.000000 tx2_gain:86.000000 OK
Note
Set command, save when power off. Different Bandwidths, Guard intervals, Convolution code rates, Data rate calculation formulas corresponding to constellations Air interface rate Rate(MBps) = (BandWidth(MHz) * 8.0/7.0) / (1+GI) * 1512/2048*log2(constellation point) * code_rate * 188/204. Taking 8MHz bandwidth as an example, different guard intervals, convolution code rates, data rates corresponding to constellations and required receiving signal-to-noise ratios
tx1_gain: Transmitter 1 gain tx2_gain: Transmitter 2 gain
Use
To dynamically adjust the output power. If the signal SNR/RSSI of the receiver is high, the output power can be reduced through the remote control link. When the SNR/RSSI of the end signal is low, increase the output power (transmitter)
Return Value,
Example: ATSG85.0,85.0_set gain 85.000000 85.000000 OK
Dynamically adjust the air interface rate, the air interface rate can be increased when the distance is short, and the air interface rate can be reduced when the distance is long (transmitter)
Return Value
Example:ATSM1,1,2_GI:1/16, CR:2/3, MOD: QAM64, OK
Remark
setting command, power off will not save.
Get Device Status Command
Format
ATGD_
Parameter
No
Use
query the current number of transmit antennas, guard interval, convolution code rate, number of constellations, transmit frequency, bandwidth, gain parameters (transmitter)
1. Enhanced data reliability option llc: 0 disable; 1 enable (requires the receiving end to enable this option at the same time, use in pairs, because more redundant data is added to enhance reliability, the video bit rate of the transmitting end should be set when this option is turned off half of) 2. Real-time priority/quality priority rt: 0 image quality priority; 1 real-time priority; 3. Bitrate: 0 let system decide; >0 specify bitrate(float) 4. I frame interval GOP: 0 let system decide; >0 specify GOP 5. Audio encoding option audio: 0 disable; 1 enable
1. Input resolution input_size: 0 let the system detect; >0 specify input size 2. Input frame rate input_rate: 0 let the system detect; > 0 specify input fps
Use
To specify the input resolution and frame rate to meet some special signal sources, or some special application needs (transmitter)
Return Value
Example: ATSI1080,25_ Input_size:1080p,input_rate: 25fps, OK
Remarks
After the user specifies the input resolution and frame rate through this command, the system will no longer detect the signal source (use with caution). The user can restore the default through the following command: ATSI0,0_Set the command and save it after power-off.
1. Transmitter: Used to specify the encoding output resolution and frame rate to meet the requirements of certain applications for zooming and frame reduction 2. Receiver: used to configure the resolution and frame rate of HDMI output
Return Value
Example: ATSO720,30_ output_size: 720p, output_rate: 30fps, OK
Remarks
1. For HDMI input only, this command is invalid for AV input 2. Output_size <= input_size; output_rate<=input_rate 3. Set the command and save it after the power is off.
Set Input Sources Command (switch HDMI / CVBS input)
Format
ATSU$(vin),$(ain)_ Example: ATSU0,1 _
Parameter
1. Video input selection VIN: 0 let the system detect; 1 force CVBS input; 2 force hdmi/SDI input 2. Audio input selection AIN: 0 let the system detect; 1 force analog input
Use
Used to meet specific application requirements (Example: HDMI/SDI input video, MIC input audio)
Return Value
Example: ATSU0,1_ ATSU0,1 OK
Remark
setting command, power-off save.
Get User Command
Format
ATGU _ Example: ATGU_
Parameter
No
Use
To query user-specific configuration
Return Value
Example: ATGU_ ATGU0,1 OK
Remark
query command return parameter description please refer to the ATSU command
1. DR2C carrier frequency freq(KHz) 200000~860000(200MHz~860MHz, 1KHz step) 2. DR900 carrier center frequency freq(KHz) 200000~1600000(200MHz~1.6GHz, 1KHz step) 3. DR2C channel bandwidth bw(KHz) 2000~8000(2MHz~8MHz, 1KHz step) 4. DR900 channel bandwidth bw(KHz) 3200~8000(3.2MHz~8MHz, 1KHz step) 5. Enhanced data reliability option llc: 0 disable; 1 enable (it is required that the transmitter should also enable this option at the same time, and use it in pairs. Since more redundant data is added to enhance reliability, the video bit rate of the transmitter should be set to when this option is turned off half of) 6. AV output system cvbs: 0 pal; 1 ntsc
Use
To set the receiver parameter
Return Value
example: ATSR320000,6000,0,0_ ATSR320000,6000,0,0 OK
Remark
setting command, save when power is off.
Get Receiver Command
Format
ATGR_
Parameter
No
ATGR_
the receiving end parameter
Return Value
Example: ATGR_ ATGR320000,6000,0,aes:0,cvbs:0 OK
Remark
1. Query command 2. Aes parameter indicates the current encryption status: 0 disable;1 enable 3. CVBS parameter Indicates the current AV output standard: 0 pal;1 ntsc
Get Bit Error Rate Command
Format
ATGB_
Parameter
No
Use
querying the bit error rate and signal strength of the dual antennas at the receiving end
1. Query commands 2. Ber1 and ber2 respectively indicate the bit error rate of each antenna, ranging from 0.0% to 100.0% 3. RSSI1 and RSSI2 respectively indicate the signal strength of each antenna, ranging from 0 to 100 4. Lock1 and Lock2 respectively indicate the signal locking status of each antenna (1 Represents signal lock)
1. IDX index: 0~7 (supports OSD overlay for 8 areas) 2. X-coordinate: 0~1919 3. Y coordinate: 0~1079 4. str: the string to be displayed at the corresponding coordinates (the space symbol is used to clear the display)
Use
on the video screen.OSD information
Return value
No
Remarks
1. The user specifies the x and y coordinates of the OSD display according to the maximum 1920×1080 pixels, and the system will correct the coordinates according to the actual display situation. 2. The ‘_’ character cannot be contained in the str parameter
Set Gain To Adjust
Format
ATSAD$(freq),$(adjust) _ Example:ATSAD700000,2.5_
Parameter
wireless central working frequency： Freq(KHz) 200000~2700000(200MHz~2.7GHz, step: 1KHz) Adjust the value(dB): ATSD cmd will subtract this value to set the wireless gain
Function
Specify and adjust the value for the wireless gain setting using by ATSD cmd
Feedback
Example: ATSAD700000,2.5_ freq:700000,adjust:2.50 OK
Comments
Setting command is still valid when stopping power or resetting.
Get Gain To Adjust
Format
ATGAD[$(freq)]_ Example:ATGAD700000_
Parameter
wireless central working frequency： Freq(KHz) 200000~2700000(200MHz~2.7GHz, step: 1KHz) When no parameter provides, it will list all the freq that have adjusted value.
Function
Inquiry adjust the value for wireless gain setting using ATSD cmd
Feedback
Example: ATGAD700000_ freq:700000,adjust:2.50 OK ATGAD_ freq:700000 750000 OK
1. How can I return to the No Password setting with 000000 indications after the change?
Reset the password to 000000 (one must not be missing) through the Parameter Configuration Panel Board. or set it through the ATSP_command
2. I see that Gain is the output power of the transmitter. Please tell me the range of settings of this parameter. All setting level (Gain) good for linear output operation? Or do you suggest some limited range for better linear operation?
The Gain of the COFDM configuration is the internal Gain, not the actual output power of the transmitter. The internal gain range is 0~89.75dB and the linear output: 1. At around 300~500MHz, the Gain is set to 89.75, and the actual output power of the transmitter module is about -5dBm. 2. At around 1000~1500MHz, the Gain is set to 89.75, and the actual output power of the transmitter module is about -6dBm to -10dBm.
3. I tried to set – B bandwidth (kHz) and E bit rate (Mbps). When I set E, the new value does not apply. So. the E setting is only for monitoring of available bitrate? if I wish to change the E (Bitrate) I have to change only B (bandwidth)? Am I right?
It is not recommended to modify the video bit rate ‘E’ directly, because if the output video bit rate is greater than the wireless air interface rate, the system will not work normally. By default, the internal video bit rate ‘E’ will be set to 0 for automatic. Customers only need to modify ‘B’ to modify the wireless parameters, and the video bit rate will automatically adapt. You can also adjust the wireless air interface rate by modifying GI and CR.
For more details on the Encoder Modulator Decoder Demodulator Module, please send an inquiry to us.
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