Battery Operated Notecarrier F and Swan

Hardware Notecarrier F
1

I am running into an issue when trying to operate my Notecarrier F and Swan combo via a 3.6v Tadiran TL-5930 Lithium battery. Everything works as intended when powering the Swan with a micro USB cable but when I apply the the Tadiran Battery to V+ and GND of the Notecarrier, the Swan does not boot up and the Notecarrier flashes red. I believe I am missing something to get it to work so any help would be greatly appreciated!

Additionally, are there any further resources regarding the ATTN/F_EN switch? This project is for a low power scenario so this could be useful. Thanks!

2

Hi @jcorcoran

From what you have described, it sounds like everything should work correctly with the Tadiran Battery connected to V+ and GND. Are you sure the Tadiran battery is at 3.6 V
? If needed perhaps issue a {"req":"card.restore"} command to the Notecard to clear any settings that may be causing problems with the F_EN pin.

Additionally, yes, you may want to have a read of this document for detailed use of the note-arduino library for controlling the F_EN pin. This guide may also be useful to you.

Thanks,
Alex

3

Thank you Alex, on my multimeter the Tadiran reads at 3.69 V. Alternatively, VMAIN only reads 2.8-2.9 V when the battery is connected and the Tadiran hovers around 2.9-3.1 V when connected to the Notecarrier which seems like a steep voltage drop. The only sign of life I am seeing on the module is the red LED Notecard flashing in bursts but the Swan seems to be off. Furthermore, how can I send the restore command to the device? Would this just be part of the uploaded device firmware?

Thank you for the document detailing F_EN.

4

@jcorcoran

I have a suspicion that the issue is not the Notecard’s configuration but perhaps the Tadiran.

I’m wondering if your Tadiran is unable to support the current draw from the Notecard, perhaps it’s worth checking what current it’s rated for? We sell a high current pulse Tadiran battery on our webstore, that might be worth testing?

To send the card.restore command you could use our web terminal by connecting the Notecarrier F to your computer and heading to the webpage. You can find out more about the card.restore command in the docs. To clean the slate, you’ll want to use both delete and connected.

Alex

1 Like
5

It was a current issue, I tested it with a 5 V power bank and everything is working smoothly now thank you. Just need to implement the correct power saving features now because deep sleep didn’t seem to be working fully using the LowPower library.

2 Likes
6

Glad we found the problem!

Let me know if you run into any issues with the power saving features.

7

Hi @abucknall, I have incorporated a few of the features you have provided earlier in my current code. However, I am running into an issue where the device is not providing a stable reading on a multimeter when in a low power state. I am getting as low as 4.7 mA but I believe I should be able to go much lower. I am using the ATTN feature with the notecarrier F and have the dip switch set to the ATTN setting as well. Are there any issues in my current code?

#include <Arduino.h>
#include <Notecard.h>

#define usbSerial Serial
#define productUID "com.gmail.jaycecorcoran:pressure_inducer"

Notecard notecard;


void setup() {
  usbSerial.begin(115200);
  delay(2000);
  notecard.begin();
  notecard.setDebugOutputStream(usbSerial);

  analogReadResolution(12); // Set ADC resolution to 12 bits
  pinMode(A1, INPUT); // Set A1 as input for the sensor

  {
  J *req = notecard.newRequest("hub.set");
  if (req != NULL) {
    JAddStringToObject(req, "product", productUID);
    JAddStringToObject(req, "mode", "minimum");
    notecard.sendRequest(req);
    }
  }
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, HIGH); // Turn on the LED to indicate setup is complete

  uint32_t raw_val = analogRead(A1); // Read the sensor once to stabilize the ADC
  J *req = notecard.newRequest("note.add");
  if (req != NULL)
  {
    JAddStringToObject(req, "file", "data.qo");
    J *body = JAddObjectToObject(req, "body");
    if (body)
    {
      JAddNumberToObject(body, "data", raw_val);
    }
    notecard.sendRequest(req);
    //sync to hub
    J *syncReq = notecard.newRequest("hub.sync");
    notecard.sendRequest(syncReq);
  }
}

void loop(){
  J *req = notecard.newRequest("card.attn");
  JAddStringToObject(req, "mode", "sleep");
  JAddNumberToObject(req, "seconds", 120); // 2 minutes

  notecard.sendRequest(req);
}

I have a MoJo and high pulse Tadiran arriving next week so I would like everything to be squared away by then hopefully.

8

@jcorcoran

How are you currently powering the Notecard?

I believe if you are testing this with USB, the Notecard will not enter its lowest power mode. I think you’ll need to try to measure the current under battery power.

“The Notecard will never go into low power (~8µA@5V) mode if VUSB is present (M.2 pin 13), or if AUX_EN (pin 56) is pulled HIGH (3v3).”

This might also point you in the right direction!

9

I exposed the wiring of a microusb cable connected to a power bank to power through the V+ pin. I will ensure AUX_EN is disabled.

10

Let me know how that goes!

I’m not sure if you’ve come across the doc but there’s a page specifically for low-power design in the docs.

It may be worth confirming that your Notecard goes into this low-power state without the Swan to begin with, adding back the Swan once you have confirmed that it is achieving the target ~8µA@5V at idle.