I have this robot car kit for my nephew. I have assembled it and I can download the Lesson 1 program, apparently successfully. When connected to USB the voltmeter reads 4.34. I have fully charged the two batteries and I can observe voltage on the battery connector pins. But when I disconnect the USB, the car goes dark. I have the switch on, and I have pushed the various buttons. What can I do to troubleshoot?
I have double-checked the connections and they all appear to be correct. The CPU is the ESP-12S. I've tried two different USB ports, no help. I'm stuck.
I am not following your question you state "I can observe voltage on the battery connector pins" That in itself is useless. Do you observe that voltage when the USB is disconnected? Can you post an annotated schematic showing exactly how you have wired it?
It is wired per the directions that came with the kit. The charging unit for the batteries says they are fully charged. I wanted to be sure the battery holder was not defective so I put the batteries in it and checked that there was voltage at its connector where it plugs into the circuit board. There was voltage.
The kit does not contain a schematic of the circuit board.
The link you posted, the very first test. You uploaded the program then unplug the usb and the car is supposed to move back and forth in a certain pattern.
There are 20 lessons on that page. Did you try Lesson 6, "Hello, World!"? Before making the whole car work, you should test each device, using Lesson 1 through 14.
I will assume you have wired it correctly and the battery is charged and good. If this is true something else is not working. Without the schematic I can't be of further help.
Lithium ion. 16500 types. I don't know the exact voltage. I don't have a meter. But it's enough to tickle my tongue, sort of like a 9V battery. The point is that the battery holder was functional and there was power at its output pins.
Adding to @v205 - The Osoyoo motor driver looks a lot like the L298N which will need 1.5v of your 8.4v to operate, leaving you with 6.9v for four motors... which look like 6v motors
(or 12v motors with a recommended operating voltage: 6V-8V.
Dronebotworkshop guy uses a 5-battery-pack (15vdc) for his kit car (kit came with 4-battery-pack) for his four 12v motors, LN298N, two servos, sonar, wifi, arduino.
The fact that the board goes dark when I unhook the USB seems odd. Is there a simple Arduino program that can confirm the chip even works? The IDE says the upload completed but it makes me wonder....
To confirm the board works, isolate it from all connections. Start the IDE. Plug the Arduino into the USB. Listen for your OS new-device tones. In the IDE, check TOOLS >> PORT >> and you should see a the port with your Arduino (if not, check device manager for your USB connections). Then TOOLS > BOARD >> Arduino AVR boards >> (your Arduino)
Remember back in Post #8 when I said there were 20 Lessons, and recommended you start with #1, but you started with #15 "Build and run" but "it didn't work"... I would start with Lesson #1.
I think you have a WiFi device attached to the expansion board (shield)... and the WiFi board might be using Arduino pins D0 and D1 (RX and TX) [edit]RX and TX are used in the USB cable for programming the Arduino[/edit]. If this is so, to program the Arduino, you will need to unplug the battery, unplug the WiFi board (8266?), plug in the USB cable, then program the Arduino... and then remove the USB, plug-in the WiFi board and plug in the battery and turn it on.
