Timeline for Controlling an RC car using Arduino
Current License: CC BY-SA 3.0
15 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 13, 2017 at 12:50 | history | edited | Community Bot |
replaced http://arduino.stackexchange.com/ with https://arduino.stackexchange.com/
|
|
| Feb 29, 2016 at 19:33 | vote | accept | Lightvvind | ||
| Feb 29, 2016 at 18:15 | history | edited | Dave X | CC BY-SA 3.0 |
added 281 characters in body
|
| Feb 29, 2016 at 18:11 | comment | added | Dave X | Ah. The Arduino's output of 5V is probably feeding too much voltage into the controller, confusing it when you have the ground connected. You will probably need something like the level-shifting in arduino.stackexchange.com/a/419/6628 | |
| Feb 29, 2016 at 14:39 | comment | added | Lightvvind | Added image of controller and arduino in the question. Can't provide a schematic for the controller unfortunately. | |
| Feb 29, 2016 at 13:58 | comment | added | Dave X | Hmm. If the controller ground is not connected, and the only connection between the two are the four controller signal lines, I'm confused. Please post a schematic and maybe a picture of your controller and connections in your Question. If only the 4 controller signal wires are connected between the two, the best I can guess is that it is storing a charge somehow relative to the other pins/device, which seems sort of magical and unreliable. | |
| Feb 29, 2016 at 12:29 | comment | added | Lightvvind | Tried connecting the controller ground to the Arduino ground and that didn't change anything. It only works when I'm using the resistors. | |
| Feb 29, 2016 at 7:58 | vote | accept | Lightvvind | ||
| Feb 29, 2016 at 12:28 | |||||
| Feb 29, 2016 at 3:10 | history | edited | Dave X | CC BY-SA 3.0 |
Add controller specs per comments, and flesh out answer.
|
| Feb 29, 2016 at 3:04 | comment | added | Dave X | A 0.54V drop across a 330 ohm resistor is 0.0016A of current, which is well within the Arduino's I/O capability. That same current through the 3.1V - 0.54V=2.56V voltage drop inside the controller implies it has about 1600 ohms of internal resistance, so you could rely on the controllers's internal protection you just measured and go without any resistor at all. I assume you connected the common ground as well -- If so, that is the main improvement. The resistor fiddling was testing that the controller would not overload your arduino. | |
| Feb 29, 2016 at 2:44 | comment | added | Lightvvind | Didn't have a 150 ohm resistor, used a 330 ohm one instead. Voltage across the resistor is 0.54V. Every possible combination of directions now works. Does it matter if it's 330 or 150 ohm? Thanks for the help, this was more complex than I thought. | |
| Feb 29, 2016 at 2:14 | comment | added | Dave X | At 3.1V, a 150 ohm resistor would limit the current to 20mA. If you can put a 150 ohm resistor between the control wire and control ground, does the motor operate normally? Also can you measure the voltage across the resistor? If it works with the 150ohm resistor, you could put the resistor in series between the control wire and the arduino input and use it as a current limiting protection resistor. | |
| Feb 29, 2016 at 2:07 | history | edited | Dave X | CC BY-SA 3.0 |
added 19 characters in body
|
| Feb 29, 2016 at 2:03 | comment | added | Lightvvind | Can't measure the current, it just shows 0. Open circuit voltage between controller's ground and control wire is 3.1V. Controller is powered by 2 1.5V batteries btw. | |
| Feb 29, 2016 at 1:53 | history | answered | Dave X | CC BY-SA 3.0 |