I have both the Adafruit motor shield v1 and the Adafruit ultimate GPS shield. I using a Leonard, and the DF Robot with 4 DC motors.
I've noticed that the RC I've built using just the Leonard + Motor Shield stacked with an Arduino wireless shield, it all works fine with plenty of power.
However, when I placed the GPS shield into the stack, I've noticed that the power isn't as good, and the wheels stutter some. Basically, it's not fluid like it previously was.
Is the ultimate GPS shield and the Motor Shield interfering with each other somehow / or competing for pins/ resources?
Motor Shield V1 & GPS Shield
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- adafruit_support_bill
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Re: Motor Shield V1 & GPS Shield
Yes, there are a number of pin conflicts between those two shields:
https://learn.adafruit.com/adafruit-motor-shield/faq
https://learn.adafruit.com/adafruit-shi ... gps-shield
The V2 motor shield uses only SDA and SCL, so it has no conflicts with the GPS shield.
https://www.adafruit.com/product/1438
https://learn.adafruit.com/adafruit-motor-shield/faq
https://learn.adafruit.com/adafruit-shi ... gps-shield
The V2 motor shield uses only SDA and SCL, so it has no conflicts with the GPS shield.
https://www.adafruit.com/product/1438
- project_science
- Posts: 190
- Joined: Sun May 04, 2014 1:26 pm
Re: Motor Shield V1 & GPS Shield
That is interesting and explains the funky behavior. Thank you.
do you know if the GPS of V2 motor shield would have conflicts stacked with the wireless shield (which I'm currently using?)
http://arduino.cc/en/Main/ArduinoWirelessShield
I haven't seen any issues, just wondering if I'm missing something before upgrading to the V2
do you know if the GPS of V2 motor shield would have conflicts stacked with the wireless shield (which I'm currently using?)
http://arduino.cc/en/Main/ArduinoWirelessShield
I haven't seen any issues, just wondering if I'm missing something before upgrading to the V2
- adafruit_support_bill
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Re: Motor Shield V1 & GPS Shield
I don't see any pin conflicts there.
- project_science
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- Joined: Sun May 04, 2014 1:26 pm
Re: Motor Shield V1 & GPS Shield
Ok, I switched to the UNO, but I don't really see the issue with the stack as it doesn't look like the pins are conflicting (perhaps you can fill me in if I am missing something).
Wireless Shield (using XBee Series 1, no SD card in use): RX,TX (assuming 0,1)
http://arduino.cc/en/Main/ArduinoWirelessShield
Motor Shield v1: 3,5,6,11
https://learn.adafruit.com/adafruit-motor-shield/faq
Ultimate GPS Shield (no SD card in use): 7, 8 (RX, TX) when using Soft Serial
https://learn.adafruit.com/adafruit-shi ... gps-shield
These shields don't seem to have overlapping pins. And they seem to leave these pins open:
2,4,9,10,12,13
So why would the motors be acting funny when using the Ultimate GPS Shield in the stack with the UNO? What could I fix?
Wireless Shield (using XBee Series 1, no SD card in use): RX,TX (assuming 0,1)
http://arduino.cc/en/Main/ArduinoWirelessShield
Motor Shield v1: 3,5,6,11
https://learn.adafruit.com/adafruit-motor-shield/faq
Ultimate GPS Shield (no SD card in use): 7, 8 (RX, TX) when using Soft Serial
https://learn.adafruit.com/adafruit-shi ... gps-shield
These shields don't seem to have overlapping pins. And they seem to leave these pins open:
2,4,9,10,12,13
So why would the motors be acting funny when using the Ultimate GPS Shield in the stack with the UNO? What could I fix?
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: Motor Shield V1 & GPS Shield
Pins 4, 7, 8 and 12 are used by the motor shield also.
What pins are not used on the motor shield?
All 6 analog input pins are available. They can also be used as digital pins (pins #14 thru 19)
Digital pin 2, and 13 are not used.
The following pins are in use only if the DC/Stepper noted is in use:
Digital pin 11: DC Motor #1 / Stepper #1 (activation/speed control)
Digital pin 3: DC Motor #2 / Stepper #1 (activation/speed control)
Digital pin 5: DC Motor #3 / Stepper #2 (activation/speed control)
Digital pin 6: DC Motor #4 / Stepper #2 (activation/speed control)
The following pins are in use if any DC/steppers are used
Digital pin 4, 7, 8 and 12 are used to drive the DC/Stepper motors via the 74HC595 serial-to-parallel latch
The following pins are used only if that particular servo is in use:
Digitals pin 9: Servo #1 control
Digital pin 10: Servo #2 control
- project_science
- Posts: 190
- Joined: Sun May 04, 2014 1:26 pm
Re: Motor Shield V1 & GPS Shield
Ok, so if I have this right, using the v2, from your earlier post, would mean that pins 7,8 would now be open (for the GPS) since v2 only uses the SDL / SCL lines? Is this correct? I'm confused by this vs. the pins used listed on the page - unless that page is for v1 only.
I would put the GPS on direct (0, 1), but the wireless shield uses them I think.
I would put the GPS on direct (0, 1), but the wireless shield uses them I think.
- adafruit_support_bill
- Posts: 88093
- Joined: Sat Feb 07, 2009 10:11 am
Re: Motor Shield V1 & GPS Shield
That page is from the V1 motor shield tutorial and applies to the V1 shield only. The V2 shield has a completely different design (and tutorial to match)
https://learn.adafruit.com/adafruit-mot ... rduino/faq
https://learn.adafruit.com/adafruit-mot ... rduino/faq
What pins are/are not used on the motor shield?
The shield uses the SDA and SCL i2c pins to control DC and stepper motors. On the Arduino UNO these are also known as A4 and A5. On the Mega these are also known as Digital 20 and 21. On the Leonardo these are also known as digital 2 and 3. Do not use those pins on those Arduinos with this shield with anything other than an i2c sensor/driver.
Since the shield uses I2C to communicate, you can connect any other i2c sensor or driver to the SDA/SCL pins as long as they do not use address 0x60 (the default address of the shield)
If you want to use the servo connections, they are on pins #9 and #10. If you do not use the connector then those pins are simply not used.
You can use any other pins for any other use
Please be positive and constructive with your questions and comments.