Sleep/Wake/TXRx Cycle

[Yveaux]

@a-lurker said:

Any one presenting measurements should indicate if they are using Ver 1.3 or 1.4 of the code.

And anyone stating rules should first read the posts with some attention; it's clearly in my post :-1:

These 3 values are sent using MySensors 1.3

[Yveaux]

@Zeph @Therik asks about thoughts on his power signature. I did a similar experiment to show him that his initial findings are, for some reason, far off.

I agree on your timing calculations (packet payloads are far shorter than 32 bytes, though), but for some reason my measurements do also not seem to agree with the calculated values.
I used default settings for the MySensors library and used version 1.3. There should be no ack but I've seen (using wireless sniffer) the receiving nRF24 send acks anyway. Still have to investigate why...
There could also be delays in the MySensors or nRF24 driver implementation (how about the crc8 calculation in MySensors 1.3? -- anyone timed it?), but these are unlikely to take several ms.

Lets try to understand and help @therik improve his application! We will all benefit from it!

Update
@hek I had a quick look at the Sensor.cpp code and all sends seem to boil down to Sensor::sendWrite.
And what's in there? "WAIT FOR ACK" which can take 50ms???

  boolean Sensor::sendWrite(uint8_t dest, message_s message, int length) {
  // ... some init code
  RF24::stopListening();
  RF24::openWritingPipe(TO_ADDR(dest));
  RF24::write(&message, min(MAX_MESSAGE_LENGTH, sizeof(message.header) + length), broadcast);
  RF24::closeReadingPipe(WRITE_PIPE); // Stop listening to write-pipe after transmit
  RF24::startListening();

  if (!broadcast) {
    // ---------------- WAIT FOR ACK ------------------
     unsigned long startedWaiting = millis();
     bool timeout = false;
     // Wait for ack message maximum 50 ms
     while ( !RF24::available() && !timeout ) {
      if (millis() - startedWaiting > ACK_MAX_WAIT ) {
        timeout = true;
        debug(PSTR("Ack: receive timeout\n"));
        ok = false;
      }
     }
     // Check payload size and content
     if (!timeout) {
       // Check payload size and content
       if (RF24::getDynamicPayloadSize()==sizeof(uint8_t)) {
       uint8_t idest;
       RF24::read( &idest, sizeof(uint8_t));
       if (dest != idest) {
         debug(PSTR("Ack: received ack from the wrong sensor\n"));
         ok = false;
       } else {
         debug(PSTR("Ack: received OK\n"));
       }
       } else {
         ok = false;
         debug(PSTR("Ack: received none ack msg.\n"));
       }
    }
  }
  return ok;
}

Can you give us a quick explanation?

[Zeph]

Yowsa.

Those three tiny spikes that go up to about 27 may be the actual transmissions, then.

[hek]

@Yveaux said:

@hek I had a quick look at the Sensor.cpp code and all sends seem to boil down to Sensor::sendWrite.
And what's in there? "WAIT FOR ACK" which can take 50ms???

This is the old inter-node ack mechanism used in 1.3 (long story why we had to do it like this). This should not be mixed up with full route ack messages used from source to final destination.

This code has been replaced by the NRF build-in ack/retransmission functionality in 1.4.

[Yveaux]

@hek OK, I'll repeat with 1.4 then!

[therik]

Hi guys,

I checked again, with another scope (1 GHz Tektronix) and I get 1.44s total time. It must be hardware or software related, not measurement related. Any other ideas to fix? I need to run the node without a gateway, because the measurement must be made off-site from vera and the gateway.

[Zeph]

@therik said:

No modification: current from battery: 2.24 mA, current to pro-mini: 1.63 mA
Remove LED: current form battery: 144 µA, current to pro-mini: 104 µA
Remove LED and regulator: current from battery: 48 µA, current to pro-mini: 23 µA

This refers to removing a power-on LED from the APM, right? (The LED from the china booster already being removed).

And you were feeding power to the APM's VCC (ie: output of it's onboard linear regulator) until the third measurement, where you removed the unused regulator as well from the APM?

That's excellent low power for a cheap booster!

Did you remove the LED and reg with a simple soldering iron?

---

Only thing is, that bottom trace looks kinda choppy. No problems with powering the radio directly from the booster?

(All this leaving aside the slow timing. I understand that 1.3's timeouts were 50ms and it probably did a bunch of them because there was nobody to respond, but why would the lower current first part - presumably doing sensor measurements - take so long?).

[Yveaux]

@therik You are running at 8Mhz, right? Maybe do a quick I/o pin toggle test to toggle it a fast as possible and measure pulse on a scope. That test we can easily repeat when in doubt.

[therik]

Okay, did the toggle test using the delayMicroseconds() method. I tested 96 µs, 1000 µs, and 10 ms and all were very close to the set delay, pins 6, 5, and 4 respectively. (@ 8 MHz the delay is a multiple of 8 µs).

It must be the fact that I'm trying the MySensors temperature sketch 'gatewayless'. I wonder if I can modify the sketch to not wait for an ACK. Of course, when I get a scope at home the 'gatewayless' operation will not be needed.

[Yveaux]

@therik What about the first part of the scope chart, starting from 0 sec?
What is the sketch doing there for more than half a second? It was reading temperatures, but for how many sensors?