3Pcs Geekcreit® HC-12 433MHz SI4438 Wireless Serial Module Wireless Transceiver Transmission Serial Communication Data Board Remote 1000M
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1. Supply volage: 3.2V~5.5V. (If he module you wa o work log hours i he emissio sae, i is recommeded ha whe he supply volage exceeds 4.5V hreaded a 1N4007 diode o preve module buil-i LDO heaed)
2. Defaul address rage (ope field es): Abou 600m (maximum commuicaio disace adjusable reach 1000m, he baud rae is 500bps)
3. Defaul idle curre: 16MA (I differe workig modes operaig curre is differe)
4. Module dimesios: 27.8 x 14.4 x 4mm
5. Operaig frequecy rage: 433.4-473.0MHz, up o 100 chaels of commuicaio
6. The maximum rasmi power: 100mW (seable)
7. Module suppor sofware upgrade
8. Defaul facory seigs: Mode FU3, baud rae is 9600bps, commuicaio chaels CH001 (433.4M)
Module parameers, AT commad se
AT commad is used o se he parameers of he fucio module ad swichig modules eed o exi he seig mode afer seig o ake effec. Meawhile, modify he parameers ad fucios, power-dow is o los.
The firs ery mode - ormal use (has he power) i he firs 5-pi "SET" is se low;
The secod mode of ery - power, 5h pi "SET" agai firs se low o power.
Boh mehods ca make he module io AT commad mode, release ("SET" pi is o coeced low) o exi commad mode. Afer he exi commad mode, if you chage he module fucio, he fucio will be cu o he appropriae sae.
The secod way is fixed i serial forma 9600, N, 1 io he AT.
1. AT
Tes isrucios
Example: Sed module commads "AT", he module reurs "OK".
2. AT + Bxxxx
Chage he serial por baud rae commad. You ca se he baud rae is 1200bps, 2400bps, 4800bps, 9600bps, 19200bps, 38400bps, 57600bps ad 115200bps. The facory defaul is 9600bps.
Example: Se he module serial por baud rae is 19200bps, please sed module commad "AT + B19200", he module reurs
"OK + B19200".
3. AT + Cxxx
Chage he wireless commuicaio chael, selecable from 001 o 127 (more ha 100 radio chaels afer he commuicaio disace o guaraeed). The defaul value is 001 radio chaels, operaig frequecy is 433.4MHz. Sep chael is 400KHz, he operaig frequecy of he chael 100 is 473.0 MHz.
Example:
Se module o chael 21, please sed module commad "AT + C021", he module reurs "OK + C021".
Afer exiig he commad mode, he module i he firs 21 chaels, operaig frequecy is 441.4 MHz.
Noe: Because he wireless receiver module sesiiviy HC-12 is relaively high, he baud rae is greaer ha whe air 58000 bps, 5 mus be shifed o he adjace chael use. Whe he air baud rae is o greaer ha 58000 bps, if he shor disace (10 meers) commuicaio, bu also eed o sagger five adjace chael use.
4. AT + FUx
Chage he module serial pass-hrough mode, here FU1, FU2 ad FU3 hree modes. Module defaul mode is FU3, wo serial pass-hrough mode module mus be se o he same commuicaio. See deailed above, "wireless serial pass-hrough" par.
Example: Sed module commads "AT + FU1", he module reurs "AT + OK".
5. AT + Px
The defaul seig is 8, maximum rasmi power, commuicaio disaces. Trasmi power level is se o 1, he miimum rasmissio power. I geeral, he rasmissio power of each drop 6dB, commuicaio disace will be reduced by half.
Example: Sed module commads "AT + P 5", he module reurs "OK + P5". Afer exiig he commad mode, he module rasmi power is +11 dBm.
u200a
u200a
3 x HC-12 module
u200a
u200a
