Mini_COFDM Ethernet module communication control protocol Vcan1886
İçindekiler
1. İletişim kontrolü seri port parametreleri
8 veri bitleri
1 biraz dur
eşit eşitlik
baud hızı: 19200
2. Module Configuration Parameters
The module configuration parameters are written by writing a 256×8 of RAM To achieve this, the configured parameters are valid after saving reset, or powering on again. Sistem açıldıktan veya sıfırlandıktan sonra, seri port yazdırılacak {AAAAA}
RAM Parameter Description
Veri deposu[0]: Sistem sıfırlama kontrolü, okunabilir ve yazılabilir, Reading and writing represent different meanings:
Yazmak
00 => Reset the whole system, Serial returns {AAAAA}, sistemin sıfırlandığını belirten
01 => Save the parameters set by the user, Serial returns {000101}, indicates successful execution
02 => Restore parameters to system default parameters, Serial returns {000202}, Başarılı yürütmeyi gösteren
03=> Search for the frequency point of the specified bandwidth. Seri port geri döner {000303}, indicates successful execution
04=> Search for the specified frequency when the parameters are known, return {000404}, indicates successful execution
05=> reloadkey, Serial port parameter setting of transmitting parameters and data serial port, returns {000505}, indicates successful execution
06=> Dynamically modify the decay parameters of the emission (write RAM[8] The attenuation value takes effect immediately after the command is issued, and does not reset the emission. After power off, and power on again, Veri deposu[8]is the previously saved value),
return{000606},Indicates successful execution
other=> reserve
read:
Biraz[0] =>
‘1’ = Transmitter RF frequency lock
‘0’= Transmitter RF Frequency not locked
Biraz[1] =>
‘1’ = Receiver RF frequency lock
‘0’= Receiver over RF Frequency not locked
Biraz[7:2] => reserve
Veri deposu[1]: Function module working state setting, and data serial port rate, okunabilir ve yazılabilir, Defaults is 0X44
Biraz[7:4]: serial speed
“0000” =1200,
“0001”=2400,
“0010”=4800,
“0011”=9600,
“0100”=19200,
“0101”=38400,
“0110”=57600,
“0111”=115200
“1000”=230400,
“1001”~”1111″=ayrılmış
Biraz[3] :Parity
‘0’=even effect test,
‘1’=mucizevi etki
Biraz[2] :parity switch
‘1’=open
‘0’=close
Biraz[1]: Receiver module working status
‘1’=Receiver module off
‘0’=Receiver module works normally
Biraz[0]: Transmitter working status
‘1’=Transmitter module off
‘0’=The transmitter module works normally
Veri deposu[2]: Transmit bandwidth, okunabilir ve yazılabilir, Defaults 0X14,
Divide the corresponding decimal number by10 The bandwidth set for, ranges from20~80, include20(2M Bandwidth) and 80(8M Bandwidth)
other=> reserve
Veri deposu[3]~RAM[4]: Transmitter module RF center frequency, readable and writable Defaults RAM[3] = 0X0D, Veri deposu[4] = 0X48
In units of 100KHz. Maksimum değer: 25000 and the minimum value is 500.
Veri deposu[5]: Transmitter module FEC Code rate, okunabilir ve yazılabilir, Defaults 0X00
00 => 1/2
01 => 2/3
02 => 3/4
03 => 5/6
04 => 7/8
other=> reserve
Veri deposu[6]: Transmitter module modulation mode, okunabilir ve yazılabilir, Defaults 0X00
00 => QPSK(4QAM)
01 => 16QAM
02 => 64QAM
other=> reserve
Veri deposu[7]: Transmitter module guard interval, okunabilir ve yazılabilir, Defaults 0X00
00 => 1/32
01 => 1/16
02 => 1/8
03 => 1/4
other=> reserve
RAM[8]: Transmitter module RF Output power attenuation value, okunabilir ve yazılabilir, The default value is0X00
00: 0 dB
01: 1 dB
02: 2 dB;
………..
0F:15 db
other=> reserve
Veri deposu[9]: Receive frequency bandwidth, okunabilir ve yazılabilir, Defaults 0X14
Divide the corresponding decimal number by10 The bandwidth set for, ranges from20~80,include20(2M Bandwidth) and80(8M Bandwidth)
other=> reserve
Veri deposu[10]~RAM[11]: receiver module RF center frequency, range 158M to 860M, Readable and writable Defaults RAM[10] = 0X0D, Veri deposu[11] = 0X48
In units of 100KHz. Maksimum değer: 90000 and the minimum value is 2000
Veri deposu[12]~RAM[21]: Receive searched channel parameters, salt okunur,
struct dibDVBTChannel {
int8_t spectrum_inversion;
int8_t nfft;
int8_t guard;
int8_t constellation;
int8_t hrch;
int8_t alpha;
int8_t code_rate_hp;
int8_t code_rate_lp;
int8_t select_hp;
int8_t intlv_native;
} dvbt;
Veri deposu[22]~RAM[37]: The encryption key, the readable and writable, Default value is all zeros
Veri deposu[22] :128 bit encryption key[127-120]bit
Veri deposu[23] :128 bit encryption key[119-112]bit
Veri deposu[24] :128 bit encryption key[111-104]bit
Veri deposu[25] :128 bit encryption key[103-96]bit
Veri deposu[26] :128 bit encryption key[95-88]bit
Veri deposu[27] :128 bit encryption key[87- 80]bit
Veri deposu[28] :128 bit encryption key[79-72]bit
Veri deposu[29] :128 bit encryption key[71-64]bit
Veri deposu[30] :128 bit encryption key[63-56]bit
Veri deposu[31] :128 bit encryption key[55-48]bit
Veri deposu[32] :128 bit encryption key[47-40]bit
Veri deposu[33] :128 bit encryption key[39-32]bit
Veri deposu[34] :128 bit encryption key[31-24]bit
Veri deposu[35] :128 bit encryption key[23-16]bit
Veri deposu[36] :128 bit encryption key[15-8]bit
Veri deposu[37] :128 bit encryption key[7-0]bit
göstermek[127-0]all for0,no encryption
Veri deposu[40]~RAM[43]: For calculating the signal-to-noise ratio, see related documents for details
Veri deposu[44]~RAM[45]: calculate RF power,rf_power Refer to the code for details
Veri deposu[46]~RAM[48]: calculate RF power,n_agc_power Specific reference code
Others RAM Reserved, cannot read or write its contents
3. Module configuration command
The configuration command is realized by sending commands to it through the serial port Command format: {+işlem kodu+RAM adresi+<işlenen>+check code+} sembol{}inside is ASCII expressed in code16 base number
{: Indicates the start of the command
+: Indicates that only the connection indicated here, for illustration, does not exist in the actual command
<>: Indicates that there is no
}: Indicates the end of the command
işlem kodu: 00 means to write, FF means to read,1 byte RAM address: 1 byte
işlenen: the operand of the command1 byte, in read operation, This byte does not
check code: (opcode+ deposit address+ <işlenen>) mod 256
command return format:
Operation successful return format: {+adresi kaydet+değeri kaydet+kodu kontrol et+}
reset command did not return
İşlem hatası dönüş formatı{FFFFFF}
4. channel size parameter calculation method reference
The maximum channel capacity of the system can be calculated using the following formula:
Rmax=6.75 x b x FEC x (188/204) x (1/(1+GD)) x (BW/8)
Rmax: The maximum capacity of the channel(Mb/s)
B: Coupling wave ratio function,QPSK hour b=2, 16QAM hour b=4,64QAMhourb=6 FEC: internal error correction code rate(1/2, 2/3, 3/4, 5/6, 7/8)
GD: guard interval1/4, 1/8, 1/16, 1/32
siyah beyaz: Bandwidth toM as a unit
According to the above formula, the maximum capacity of the channel can be calculated under a few parameters. As shown in the table below, yes8mInformation capacity under bandwidth. The system will automatically calculate the size of the coded output stream according to the set channel parameters so that the size of the output stream is not greater than the maximum capacity of the channel.
5. Not
on the board L19 location (at U9 On the side, the position is empty when leaving the factory) can add a 0603 The inductance to increase the output power, the increased inductance value can refer to the following figure
Kablosuz Video İletim
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