Battery Sensor v 1.0 PCB

[axillent]

@clippermiami do not knew why but there are a few versions of this example
try this one

sorry, do not knew how to insert a code here

/*
 Copyright (C) 2011 James Coliz, Jr. <maniacbug@ymail.com>
 Copyright (c) 2012 Greg Copeland

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 version 2 as published by the Free Software Foundation.
 */

/**
 * Channel scanner
 *
 * Example to detect interference on the various channels available.
 * This is a good diagnostic tool to check whether you're picking a
 * good channel for your application.
 *
 * Inspired by cpixip.
 * See http://arduino.cc/forum/index.php/topic,54795.0.html
 */

#include <SPI.h>
#include "RF24.h"
#include "printf.h"

// Only display active frequencies
static const bool activeOnly = true ;

//
// Hardware configuration
//

// Set up nRF24L01 radio on SPI bus plus pins 8 & 9

RF24 radio(9,10);

//
// Channel info
//

const short num_channels = 128;
short values[num_channels];
uint8_t signalMeter[55] ;

//
// Setup
//

void setup(void)
{
  //
  // Print preamble
  //

  Serial.begin(115200);
  printf_begin();
  printf("\n\rRF24/examples/scanner/\n\r");

  //
  // Setup and configure rf radio
  //

  radio.begin();
  radio.powerUp() ;
  radio.setAutoAck(false);

  // Get into standby mode
  radio.openReadingPipe( 0, 0xFFFFFFFFFFULL ) ;
  //  radio.setDataRate( RF24_250KBPS ) ; // may fallback to 1Mbps
  radio.setDataRate( RF24_1MBPS ) ; // may fallback to 1Mbps
  radio.startListening() ;
  radio.stopListening() ;
}

//
// Loop
//
void loop(void)
{
  // Clear measurement values
  memset( values, 0x00, num_channels ) ;
  printf( "Scanning all available frequencies..." ) ;

  // Repeatedly scan multiple channels
  for( int channel=0 ; channel < num_channels; channel++ ) {
    radio.setChannel( channel ) ;

    // Amplify the signal based on carrier bandwidth
    int ampFactor ;
    for( int amp=0; amp <= 300; amp++ ) {
      // Alternate data rates
      ampFactor = amp%3 ;
      switch( ampFactor ) {
      case 0:
	radio.setDataRate( RF24_250KBPS ) ;
	break ;

      case 1:
	radio.setDataRate( RF24_1MBPS ) ;
	break ;

      default:
	radio.setDataRate( RF24_2MBPS ) ;
	break ;
      }

      // Listen for carrier
      ampFactor++ ;
      radio.startListening() ;
      delayMicroseconds( 6 - ampFactor ) ;
      radio.stopListening() ;

      // Was carrier detected? If so, signal level based on bandwidth
      if( radio.testRPD() ) {
	values[channel] += ampFactor ;
      }
    }
  }

  // Now display our results
  printf( "Scan completed.\r\n" ) ;
  for( int channel=0 ; channel < num_channels; channel++ ) {
    if( !activeOnly || (activeOnly && values[channel] > 0) ) {
      memset( signalMeter, '*', min( values[channel], 54 ) ) ;
      signalMeter[min(values[channel], 54)] = 0x00 ;
      printf( "%03d (%4dMhz): %02d - %s\r\n",
	      channel,
	      2400+channel,
	      values[channel],
	      signalMeter ) ;

      // Reset the scanned value since its already beend displayed
      values[channel] = 0 ;
    }
  }
}

// vim:ai:cin:sts=2 sw=2 ft=cpp

[clippermiami]

@axillent First thing I see is that this version has the radio on pins 8,9 whereas the version I used has it on pins 9,10 which is where it is in my hardware.

[axillent]

@clippermiami That is a good point. But something tells me that you do need an assistance to adjust this code to your hardware :)

[clippermiami]

@axillent I won't deny that, but it seems simple enough. :)

[clippermiami]

So i breadboarded a Nano and a NRFL2401 with a PA and antenna, uploaded the scanner sketch and this is what I got: I'm using the default radio channel from the distribution library.

 RF24/examples/scanner/
 Scanning all available frequencies...Scan completed.
 000 (2400Mhz): 96 - ******************************************************     
 001 (2401Mhz): 100 - ******************************************************
 002 (2402Mhz): 95 - ******************************************************
 003 (2403Mhz): 99 - ******************************************************     
 004 (2404Mhz): 98 - ******************************************************
 005 (2405Mhz): 104 - ******************************************************
 006 (2406Mhz): 91 - ******************************************************
 007 (2407Mhz): 95 - ******************************************************
 008 (2408Mhz): 98 - ******************************************************
 009 (2409Mhz): 96 - ******************************************************
 010 (2410Mhz): 96 - ******************************************************
 011 (2411Mhz): 86 - ******************************************************
 012 (2412Mhz): 89 - ******************************************************
 013 (2413Mhz): 94 - ******************************************************
 014 (2414Mhz): 95 - ******************************************************
 015 (2415Mhz): 92 - ******************************************************
 016 (2416Mhz): 93 - ******************************************************
 017 (2417Mhz): 92 - ******************************************************
 018 (2418Mhz): 99 - ******************************************************
 019 (2419Mhz): 85 - ******************************************************
 020 (2420Mhz): 99 - ******************************************************
 021 (2421Mhz): 96 - ******************************************************
 022 (2422Mhz): 90 - ******************************************************
 023 (2423Mhz): 98 - ******************************************************
 024 (2424Mhz): 85 - ******************************************************
 025 (2425Mhz): 99 - ******************************************************
 026 (2426Mhz): 100 - ******************************************************
 027 (2427Mhz): 95 - ******************************************************
 028 (2428Mhz): 95 - ******************************************************
 029 (2429Mhz): 90 - ******************************************************
 030 (2430Mhz): 95 - ******************************************************
 031 (2431Mhz): 96 - ******************************************************
 032 (2432Mhz): 95 - ******************************************************
 033 (2433Mhz): 91 - ******************************************************
 034 (2434Mhz): 93 - ******************************************************
 035 (2435Mhz): 97 - ******************************************************
 036 (2436Mhz): 104 - ******************************************************
 037 (2437Mhz): 99 - ******************************************************
 038 (2438Mhz): 92 - ******************************************************
 039 (2439Mhz): 96 - ******************************************************
 040 (2440Mhz): 94 - ******************************************************
 041 (2441Mhz): 100 - ******************************************************
 042 (2442Mhz): 92 - ******************************************************
 043 (2443Mhz): 100 - ******************************************************
 044 (2444Mhz): 110 - ******************************************************
 045 (2445Mhz): 92 - ******************************************************
 046 (2446Mhz): 111 - ******************************************************
 047 (2447Mhz): 99 - ******************************************************
 048 (2448Mhz): 98 - ******************************************************
 049 (2449Mhz): 93 - ******************************************************
 050 (2450Mhz): 97 - ******************************************************
 051 (2451Mhz): 99 - ******************************************************
 052 (2452Mhz): 93 - ******************************************************
 053 (2453Mhz): 96 - ******************************************************
 054 (2454Mhz): 93 - ******************************************************
 055 (2455Mhz): 94 - ******************************************************
 056 (2456Mhz): 106 - ******************************************************
 057 (2457Mhz): 101 - ******************************************************
 058 (2458Mhz): 94 - ******************************************************
 059 (2459Mhz): 106 - ******************************************************
 060 (2460Mhz): 91 - ******************************************************
 061 (2461Mhz): 96 - ******************************************************
 062 (2462Mhz): 98 - ******************************************************
 063 (2463Mhz): 100 - ******************************************************
 064 (2464Mhz): 107 - ******************************************************
 065 (2465Mhz): 101 - ******************************************************
 066 (2466Mhz): 93 - ******************************************************
 067 (2467Mhz): 90 - ******************************************************
 068 (2468Mhz): 102 - ******************************************************
 069 (2469Mhz): 103 - ******************************************************
 070 (2470Mhz): 95 - ******************************************************
 071 (2471Mhz): 102 - ******************************************************
 072 (2472Mhz): 99 - ******************************************************
 073 (2473Mhz): 94 - ******************************************************
 074 (2474Mhz): 97 - ******************************************************
 075 (2475Mhz): 105 - ******************************************************
 076 (2476Mhz): 97 - ******************************************************
 077 (2477Mhz): 92 - ******************************************************
 078 (2478Mhz): 103 - ******************************************************
 079 (2479Mhz): 94 - ******************************************************
 080 (2480Mhz): 98 - ******************************************************
 081 (2481Mhz): 99 - ******************************************************
 082 (2482Mhz): 103 - ******************************************************
 083 (2483Mhz): 98 - ******************************************************
 084 (2484Mhz): 89 - ******************************************************
 085 (2485Mhz): 97 - ******************************************************
 086 (2486Mhz): 94 - ******************************************************
 087 (2487Mhz): 97 - ******************************************************
 088 (2488Mhz): 92 - ******************************************************
 089 (2489Mhz): 101 - ******************************************************
 090 (2490Mhz): 98 - ******************************************************
 091 (2491Mhz): 99 - ******************************************************
 092 (2492Mhz): 92 - ******************************************************
 093 (2493Mhz): 88 - ******************************************************
 094 (2494Mhz): 95 - ******************************************************
 095 (2495Mhz): 92 - ******************************************************
 096 (2496Mhz): 95 - ******************************************************
 097 (2497Mhz): 95 - ******************************************************
 098 (2498Mhz): 90 - ******************************************************
 099 (2499Mhz): 100 - ******************************************************
 100 (2500Mhz): 94 - ******************************************************
 101 (2501Mhz): 107 - ******************************************************
 102 (2502Mhz): 90 - ******************************************************
 103 (2503Mhz): 95 - ******************************************************
 104 (2504Mhz): 105 - ******************************************************
 105 (2505Mhz): 99 - ******************************************************
 106 (2506Mhz): 101 - ******************************************************
 107 (2507Mhz): 100 - ******************************************************
 108 (2508Mhz): 103 - ******************************************************
 109 (2509Mhz): 99 - ******************************************************
 110 (2510Mhz): 99 - ******************************************************
 111 (2511Mhz): 92 - ******************************************************
 112 (2512Mhz): 90 - ******************************************************
 113 (2513Mhz): 96 - ******************************************************
 114 (2514Mhz): 102 - ******************************************************
 115 (2515Mhz): 96 - ******************************************************
 116 (2516Mhz): 91 - ******************************************************
 117 (2517Mhz): 98 - ******************************************************
 118 (2518Mhz): 95 - ******************************************************
 119 (2519Mhz): 101 - ******************************************************
 120 (2520Mhz): 104 - ******************************************************
 121 (2521Mhz): 93 - ******************************************************
 122 (2522Mhz): 98 - ******************************************************
 123 (2523Mhz): 98 - ******************************************************
 124 (2524Mhz): 96 - ******************************************************
 125 (2525Mhz): 95 - ******************************************************
 126 (2526Mhz): 94 - ******************************************************
 127 (2527Mhz): 96 - ******************************************************

Which does not look much like the display at the reference: http://arduino.cc/forum/index.php/topic,54795.0.html

and i'm not sure what its telling me other than some relative signal level data. Perhaps someone could help me interpret this :)

Updagte:
As it continues to run it shows significantly different values over time, some reaching as high as

 063 (2463Mhz): 84 - ******************************************************
 064 (2464Mhz): 89 - ******************************************************
 065 (2465Mhz): 97 - ******************************************************     
 066 (2466Mhz): 201 - ******************************************************
 067 (2467Mhz): 252 - ******************************************************
 068 (2468Mhz): 300 - ******************************************************
 069 (2469Mhz): 284 - ******************************************************

[clippermiami]

I'm about idea'd out. I put a 200 uF electrolytic directly on the Vcc and Gnd terminals of the radio module and it made no difference whatsoever ... the sensor fails to report beyond about 10 meters and one interior wall. That doesn't leave much upside.

I'm at a loss at this point, I've tried different radio modules to no avail. I've taken the radio off the board ground plane to no avail.Thus far the only thing I've found that allows decent distance is a radio with the PA/SMA antenna and that simply eats battery. I can't make hide nor hair out of the scanner output ... the channel variation doesn't appear to be more than a few percent for the most part so it doesn't look like that's much of a solution.

I admit to being curious if anyone has actually had these things work beyond the workbench :)

[Yveaux]

@clippermiami said:

I admit to being curious if anyone has actually had these things work beyond the workbench :)

Maybe your house is just a lot bigger than ours :office: :laughing:

[clippermiami]

@Yveaux While I suppose that's possible 10-15 feet is still 10-15 feet :-)

[Zeph]

@clippermiami said:

I'm about idea'd out. I put a 200 uF electrolytic directly on the Vcc and Gnd terminals of the radio module and it made no difference whatsoever ... the sensor fails to report beyond about 10 meters and one interior wall.

Do you know what's inside that one interior wall? Could it have anything which would interfere with RF (more than the typical wood 2x4's and two sheets of drywall do)?

Some people have definitely had better results.

I think you said that you had changed out the radio module, but did you try any from a different source or batch?

[clippermiami]

@Zeph it's just ordinary drywall. In the interest of complete disclosure, there is a floor-ceiling bookcase on the wall but if this stuff is THAT sensor then ... :-)

The radios are all from an order about a month ago so they are probably the same batch. I have another batch of 10 coming but that's probably a week away yet.

About the only thing left is to change radio channels but the numbers the scan don't tell me much, they don't vary but a few percent, so I am at a loss where to go.

[Yveaux]

@clippermiami I hope to release a network sniffer for NRF24 in the near future which might probably help you to diagnose the problem. It captures all on-air packets and also shows which ones have CRC errors.
The amount of packets with CRC errors is a good indication of the link quality.

[clippermiami]

@Yveaux thanks, I look forward to it :-)

[daulagari]

@clippermiami: How about ACI, Adjacent Channel Interference?

Having a WiFi background I know the 2.4 GHz band is also used by others, microwave oves, WiFi, Bluetooth etc.

Been working on WiFi - Bluetooth coexistence and although they do not share channels, Bluetooth transmitting on 10 dBm can impact WiFi dramatically if the separation of the two devices is small.

You could try moving both devices at least 5 meters away from other equipment and see if it makes a difference.

[clippermiami]

@daulagari A possibility. I have three separate Wifi Access Points running in the house two 2.4 GHz 802.11n and one 5 GHz 802.11a. The 11A and one of the 11N points are in a dual band device, the other 11N is part of my AT&T uVerse router. I have them forced to specific channels, but none of then adjacent to the MySensors default (CH 76 as I recall), the highest one is the 11A on Ch 36

[clippermiami]

I did have a chance for one more experiment. I had a SEEED "DevDuino" I bought to play with but haven't used yet. I swapped the radio from that module onto my sensor board and I was able to get reporting from another 10 feet away so there is definitely something related to the individual NRF24L01 modules --- different batch I guess. It still doesn't get me to even the other end of the house (perhaps 20 meters from the GW) let alone outside anywhere.or through outside walls.

[daulagari]

@clippermiami said:

I have them forced to specific channels, but none of then adjacent to the MySensors default (CH 76 as I recall), the highest one is the 11A on Ch 36

The NRF24 channels (Freq [MHz] = 2400 + channel) are not the same as WiFi channels. Ch 36 for WiFi is in the 5GHz band but can you share the 11n channels you forced the AP's to?

See also https://en.wikipedia.org/wiki/List_of_WLAN_channels for a list of WiFi channels and their frequencies.

[clippermiami]

@daulagari Yes, my error, 36 is in the 5GHz band.

The 2.4 GHz channels are 5 and 11. There are some neighbors' Wifi on Ch 1 and 2 but they are heavily attenuated.

[clippermiami]

It occurred to me that the one thing I had not changed was the GW radio. I had one spare NRF24L01+PA+SMA so I swapped it in the GW. That appears to be the fix --- I can now see the sensor module all the way out in the yard at the far end of the house, through outside walls and a half dozen interior walls. I doubt i'll get the 450+ meters reported elsewhere on the forum but its a LOT better than the 10 feet I was getting :)

[hek]

@clippermiami

Sounds good!

[clippermiami]

@hek just my luck, the USB on my Vera Lite has packed up so now I can"t do any more testing until I sort that out. Maddening