CC1101 - Pocsag - No TX Output

[mkrebbers]

Hey There,

I am working on a Pocsag transmitter with ESP32 and CC1101. However i cant get TX output from CC1101 using the example.
Transmitting in general is working properly (AX25,FSK,..). To check if there is any transmittion i am using SDR with dedicated antenna but the waterfall keeps flat.

Pins checked, Radio initialized, CLI shows "transmitted"

Any ideas on that?

Marc

[jgromes]

What does the code look like? Are there any errors? And did you check output in debug mode?

[mkrebbers]

This is the Code from the Example just modified to the CC1101. At the moment i cant see a problem in the main.cpp.

Waterfall:

/*
   RadioLib Pager (POCSAG) Transmit Example

   This example sends POCSAG messages using SX1278's
   FSK modem.

   Other modules that can be used to send POCSAG:
    - SX127x/RFM9x
    - RF69
    - SX1231
    - CC1101 used
    - SX126x
    - nRF24
    - Si443x/RFM2x
    - SX128x

   For default module settings, see the wiki page
   https://github.com/jgromes/RadioLib/wiki/Default-configuration

   For full API reference, see the GitHub Pages
   https://jgromes.github.io/RadioLib/
*/

// include the library
#include <RadioLib.h>

// CC1101 has the following connections:
// NCS pin:    5
// GDO0 pin:  4
// RST pin:   NC
// GDO2 pin:  2
CC1101 radio = new Module(5, 4, RADIOLIB_NC, 2);


// create Pager client instance using the FSK module
PagerClient pager(&radio);

void setup() {
  Serial.begin(9600);

  // initialize CC1101 with default settings
  Serial.print(F("[CC1101] Initializing ... "));
  int state = radio.begin();

  if(state == RADIOLIB_ERR_NONE) {
    Serial.println(F("success!"));
  } else {
    Serial.print(F("failed, code "));
    Serial.println(state);
    while(true);
  }

  // initialize Pager client
  Serial.print(F("[Pager] Initializing ... "));
  // base (center) frequency:     440.0 MHz testing!
  // speed:                       1200 bps
  state = pager.begin(440.0, 1200);
  if(state == RADIOLIB_ERR_NONE) {
    Serial.println(F("success!"));
  } else {
    Serial.print(F("failed, code "));
    Serial.println(state);
    while(true);
  }
}

void loop() {
  Serial.print(F("[Pager] Transmitting messages ... "));

  // the simples form of "message" is just a tone on the destination pager
  int state = pager.sendTone(1234567);

  if(state == RADIOLIB_ERR_NONE) {
    Serial.println(F("success!"));
  } else {
    Serial.print(F("failed, code "));
    Serial.println(state);
  }

  // wait for a second before transmitting again
  delay(1000);
}

This is the Output on Serial:

RadioLib Debug Info
Version: 6.3.0.0
Platform: ESP32
Compiled: Dec 21 2023 14:57:11
M CC1101
success!
[Pager] Initializing ... success!
[Pager] Transmitting messages ... success!

[jgromes]

Could you enable both debug nad verbose? That will show all the SPI transactions.

[mkrebbers]

Sure! I inserted a while so that the sendTone was only processed one time and then paused with the state "RADIOLIEB_ERR_NONE".
With verbose mode i cant see the success message on transmitting. If i switch it off again everything is normal.
The phrases from CMD W 35 0F keep on repeating in the console.

This is what came out:

[CC1101] Initializing ...
RadioLib Debug Info
Version: 6.3.0.0
Platform: ESP32
Compiled: Dec 21 2023 17:01:41

R 71 14
M CC1101
CMD W 30 2F
CMD W 36 0F
R 75 1
R 18 4
W 18 14
R 18 14
R 18 14
W 18 14
R 18 14
R 2 3F
W 2 2E
R 2 2E
R 0 29
W 0 2E
R 0 2E
R 7 4
W 7 4
R 7 4
R 8 45
W 8 5
R 8 5
R 8 5
W 8 5
R 8 5
CMD W 36 0F
R D 1E
W D 10
R D 10
R E C4
W E B1
R E B1
R F EC
W F 3B
R F 3B
R 3E C6
W 3E C0
R 3E C0
CMD W 36 0F
R 10 8C
W 10 87
R 10 87
R 11 22
W 11 83
R 11 83
CMD W 36 0F
R 10 87
W 10 F7
R 10 F7
CMD W 36 0F
R 15 47
W 15 17
R 15 17
R 15 17
W 15 14
R 15 14
R 3E C0
W 3E C0
R 3E C0
R 8 5
W 8 5
R 8 5
R 6 FF
W 6 3F
R 6 3F
R 7 4
W 7 64
R 7 64
R 13 22
W 13 2
R 13 2
CMD W 36 0F
R 75 1
R 12 2
W 12 2
R 12 2
CMD W 36 0F
R 75 1
R 12 2
W 12 2
R 12 2
R 8 5
W 8 5
R 8 5
R 12 2
W 12 2
R 12 2
R 4 D3
W 4 12
R 4 12
R 5 91
W 5 AD
R 5 AD
CMD W 3A 0F
CMD W 3B 0F
success!
[Pager] Initializing ... CMD W 36 0F
R 75 1
R 12 2
W 12 2
R 12 2
R 8 5
W 8 5
R 8 5
CMD W 36 0F
R 75 1
R 12 2
W 12 2
R 12 2
CMD W 36 0F
R 15 14
W 15 4
R 15 4
R 15 4
W 15 0
R 15 0
success!
[Pager] Transmitting messages ... W D 10
W E EC
W F 43
CMD W 35 0F
CMD W 36 4F
R 2 2E
W 2 B
R 2 B
R 0 2E
W 0 C
R 0 C
R 8 5
W 8 15
R 8 15
R 8 15
W 8 16
R 8 16
CMD W 35 0F
W D 10
W E EC
W F 59
CMD W 35 2F
CMD W 36 2F
R 2 B
W 2 B
R 2 B
R 0 C
W 0 C
R 0 C
R 8 16
W 8 16
R 8 16
R 8 16
W 8 16
R 8 16
CMD W 35 0F

[jgromes]

@mkrebbers thank you, this made everything clear. There was a bug that caused direct transmission to not work correctly on CC1101 (instead of exiting immediately after changing the frequency, the library tried to re-eanble direct mode). I pushed a fix for this and testing on my CC1101 setup, it seems to be working correctly, though please let me know if you find any other issues.

[mkrebbers]

@jgromes thank you for fixing it so fast! For me its working with C1101 and also the Pager is decoding.