I was playing with this new USB to TTL serial cable today and remembered seeing the USB Power Gauge Mini-Kit saying you can read data off the TX pin. I'm pretty new to this but was wondering if someone could tell what I'm doing wrong in seeing those reading. What I've done so far is download the 10.8 (I'm running Mountain Lion) serial driver for this USB to serial cable and when I plug it in I'm seeing it show up in my /dev list:
/dev/tty.NoZAP-PL2303-000032FD
I'm using the screen command to try to connect but I'm just getting a blank screen with no info coming through.
screen /dev/tty.NoZAP-PL2303-000032FD 9600 8N1
I've plugged the USB to TTL Serial cable into the USB Power Gauge Mini-Kit headers (Red-5V, Green-TX, and Black-GND) (white not plugged in since there is now RX header on the power gauge). Maybe my screen command is not quite right? Anyone using a mac have any suggestions?
From Adafruit description on the USB Power Gauge Mini-Kit:
"As an awesome extra, we also print out the voltage, current and wattage data as readable text on the TX pin at 9600 baud. Connect an FTDI friend, USB console cable, microcontroller, XBee, whatever you want that can read 9600 baud TTL serial data for datalogging, plotting or display."
USB Power Gauge Mini-Kit
http://www.adafruit.com/products/1549
USB to TTL Serial Cable - Debug / Console Cable for Raspberry Pi
http://www.adafruit.com/products/954
Reading data on TX on USB Power Gauge Mini-Kit
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- minwedar
- Posts: 12
- Joined: Fri Nov 15, 2013 11:50 pm
- adafruit_support_bill
- Posts: 88154
- Joined: Sat Feb 07, 2009 10:11 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
White is Rx with respect to the USB port. You want to connect that to the Tx coming from the power gauge.There are four wires: red power, black ground, white RX into USB port, and green TX out of the USB port.
http://www.adafruit.com/products/954#Technical_Details
There are four wires: red power, black ground, white RX into USB port, and green TX out of the USB port.
- minwedar
- Posts: 12
- Joined: Fri Nov 15, 2013 11:50 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
Thank You! That makes sense now. And I noticed I don't need the 5V and GND either, just the the White RX on the TX pin and I'm getting readings.
Arduino
V: 5.5 I: 68 mA Watts: 0.4
V: 5.5 I: 66 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 66 mA Watts: 0.4
V: 5.5 I: 67 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 69 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 70 mA Watts: 0.4
V: 5.5 I: 62 mA Watts: 0.3
V: 5.5 I: 67 mA Watts: 0.4
V: 5.5 I: 70 mA Watts: 0.4
V: 5.4 I: 68 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
Plugging in iPhone:
V: 5.5 I: 0 mA Watts: 0.0
V: 5.2 I: 383 mA Watts: 2.0
V: 5.1 I: 717 mA Watts: 3.6
V: 5.1 I: 587 mA Watts: 3.0
V: 5.3 I: 414 mA Watts: 2.2
V: 5.3 I: 487 mA Watts: 2.6
V: 5.3 I: 297 mA Watts: 1.6
V: 5.3 I: 383 mA Watts: 2.0
V: 5.3 I: 192 mA Watts: 1.0
V: 5.4 I: 174 mA Watts: 0.9
V: 5.4 I: 169 mA Watts: 0.9
V: 5.4 I: 452 mA Watts: 2.4
V: 5.3 I: 208 mA Watts: 1.1
V: 5.4 I: 157 mA Watts: 0.8
V: 5.5 I: 157 mA Watts: 0.9
V: 5.3 I: 181 mA Watts: 1.0
V: 5.4 I: 207 mA Watts: 1.1
Arduino
V: 5.5 I: 68 mA Watts: 0.4
V: 5.5 I: 66 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 66 mA Watts: 0.4
V: 5.5 I: 67 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 69 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
V: 5.5 I: 70 mA Watts: 0.4
V: 5.5 I: 62 mA Watts: 0.3
V: 5.5 I: 67 mA Watts: 0.4
V: 5.5 I: 70 mA Watts: 0.4
V: 5.4 I: 68 mA Watts: 0.4
V: 5.4 I: 67 mA Watts: 0.4
Plugging in iPhone:
V: 5.5 I: 0 mA Watts: 0.0
V: 5.2 I: 383 mA Watts: 2.0
V: 5.1 I: 717 mA Watts: 3.6
V: 5.1 I: 587 mA Watts: 3.0
V: 5.3 I: 414 mA Watts: 2.2
V: 5.3 I: 487 mA Watts: 2.6
V: 5.3 I: 297 mA Watts: 1.6
V: 5.3 I: 383 mA Watts: 2.0
V: 5.3 I: 192 mA Watts: 1.0
V: 5.4 I: 174 mA Watts: 0.9
V: 5.4 I: 169 mA Watts: 0.9
V: 5.4 I: 452 mA Watts: 2.4
V: 5.3 I: 208 mA Watts: 1.1
V: 5.4 I: 157 mA Watts: 0.8
V: 5.5 I: 157 mA Watts: 0.9
V: 5.3 I: 181 mA Watts: 1.0
V: 5.4 I: 207 mA Watts: 1.1
- adafruit_support_bill
- Posts: 88154
- Joined: Sat Feb 07, 2009 10:11 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
Assuming that you are monitoring from the same computer, that should be fine. If for some reason you wanted to monitor using a different computer, you should at least connect the ground pin.And I noticed I don't need the 5V and GND either, just the the White RX on the TX pin and I'm getting readings.
- wbp
- Posts: 260
- Joined: Mon Mar 07, 2011 1:18 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
I have a similar setup, USB Power Gauge and USB Serial cable. It works when both devices are plugged in to my PC, but I want to measure the current while the USB Power Gauge is plugged in to an external battery pack with a USB port. Using PuTTY with the same settings that worked with both plugged in to the PC, I don't get any text now. I metered the 5V pin and there is 5V (4.98, close enough).
Do I need to connect the red wire from the USB Serial cable? I wanted to check with you first so I don't fry anything...
Thanks!
William
Do I need to connect the red wire from the USB Serial cable? I wanted to check with you first so I don't fry anything...
Thanks!
William
- wbp
- Posts: 260
- Joined: Mon Mar 07, 2011 1:18 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
I should add that I have only the green and white wires connected to the USB Power Gauge at the moment.
- wbp
- Posts: 260
- Joined: Mon Mar 07, 2011 1:18 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
Followup: don't know why the USB Serial Cable doesn't work, but I also have an FTDI Friend, so I hooked that up, connecting only ground and RX, and that works just fine.
- adafruit_support_bill
- Posts: 88154
- Joined: Sat Feb 07, 2009 10:11 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
Ground and Rx should be sufficient. You don't want to be powering the device from two different sources at the same time.Do I need to connect the red wire from the USB Serial cable?
- conurus
- Posts: 4
- Joined: Wed Oct 28, 2015 4:31 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
I am getting a "Not calibrated" message from the TX port. Is it supposed to be calibrated before it leaves the factory? If not what is the calibration procedure? Thanks.
- adafruit2
- Posts: 22200
- Joined: Fri Mar 11, 2005 7:36 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
Conurus, can you paste the exact output from the TX pin? and if you can, a photo of the power gauge? they outta be calibrated during test so thats unusual :)
- conurus
- Posts: 4
- Joined: Wed Oct 28, 2015 4:31 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
Code: Select all
ÿAdafruit USB Power Meter
Oct 1 2013
Not calibrated
- conurus
- Posts: 4
- Joined: Wed Oct 28, 2015 4:31 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
So, may I send it back for a calibration please?
- adafruit2
- Posts: 22200
- Joined: Fri Mar 11, 2005 7:36 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
please hold on another day - we wnat to make sure we have our test procedure in order so your replacement *is* calibrated :)
- conurus
- Posts: 4
- Joined: Wed Oct 28, 2015 4:31 am
Re: Reading data on TX on USB Power Gauge Mini-Kit
Thank you! Are we ready yet?
But make no haste as even with only the LEDs they have already saved my butt on my design and I could not have been happier. I specifically need high side current monitoring with easy read out, and this is it!
It is just that, being a geek, I would like to explore more with the TX output. (Who wouldn't?)
But make no haste as even with only the LEDs they have already saved my butt on my design and I could not have been happier. I specifically need high side current monitoring with easy read out, and this is it!
It is just that, being a geek, I would like to explore more with the TX output. (Who wouldn't?)
- adafruit2
- Posts: 22200
- Joined: Fri Mar 11, 2005 7:36 pm
Re: Reading data on TX on USB Power Gauge Mini-Kit
ok lets try to send you another one - email support@adafruit with a link to this thread. still not sure whats up with yours! :)
Please be positive and constructive with your questions and comments.