Paul & Sabrina's cheap DIY 144v motor controller

[flores]

Paul, you build it..

Here is a picture of the blue wire for the precharge



And where is this yellow wire for? Contactor? How do I use that?


Thanks

[jedsmd]

I need a little help.
I have completed a controller board Rev C. with a ATMega 168 chip.

Not knowing how to use the bootloader in RTD Explorer, I installed coug-unified-16k.hex using AVRdude through a USBasp.

LEDs are working as expected including hi-pedal lockout, so I think the install went okay.

The problem is that RTD Explorer will not talk with the controller board at all. I am using an older laptop with a serial port and Vista. Also fails with my newer laptop and USB/Serial convertor.

From my laptop I can do a serial port loopback test all the way to pins 13 and 14 of U4 the RS232 transceiver. So I think the cable and connectors are okay. I have visually inspected solder joints and component layout at and around U4.

So I don’t know much about serial communication or microprocessors and would really appreciate any suggestions on what I could check.
Thanks
Jerald

[z_power]

This might be not the issue but did you check the fusebits? I don't know if they could mess serial communication but they're worth checking.

[jedsmd]

Originally Posted by z_power

This might be not the issue but did you check the fusebits? I don't know if they could mess serial communication but they're worth checking.

I have redone the bootload several times. When I do AVRdude reports that the fuse bits are intact.
Jerald

[mora]

I was not able to establish serial communication between computer and controller when fuse bits were not set correctly. Good indication about wrong fuses was slowly flashing led. Can't remember which one though. It flashed like one time per second. It should flash like 10 times a second. I think controller works like that but it is much slower as it doesn't utilize external oscillator.

[jedsmd]

Originally Posted by mora

I was not able to establish serial communication between computer and controller when fuse bits were not set correctly. Good indication about wrong fuses was slowly flashing led. Can't remember which one though. It flashed like one time per second. It should flash like 10 times a second. I think controller works like that but it is much slower as it doesn't utilize external oscillator.

No fuse bits are set, this is the first mention I have heard of setting fuse bits.

Is setting the fuse bits part of bootloading? I only bootloaded to flash memory so it would not have been able to set any fuse bits if was supposed to. Does anyone know how to set the fuse bits?

[flores]

Originally Posted by jedsmd

No fuse bits are set, this is the first mention I have heard of setting fuse bits.

Is setting the fuse bits part of bootloading? I only bootloaded to flash memory so it would not have been able to set any fuse bits if was supposed to. Does anyone know how to set the fuse bits?

The software you use to flash the atmega should have options for the fuse bits.

[mora]

I haven't used AVRdude but it seems to have GUI for easier fuse setting. See avrdude-gui - Browse /avrdude-gui/avrdude-gui_0.2.0 at SourceForge.net
Quick googling showed no simple command line parameter for fuses. You'd have to know what each fuse does.

[jedsmd]

Yes I can probably figure out how to set the fuse bits. If I knew what the settings need to be

Or I would prefer to use the RTD Explorer bootloader, if I could get help with how to hook it up to the controller board ISP port.

[mora]

Fuse group: setting in hex (and binary)

Extended: F8 (1111 1000)
High: DC (1101 1100)
Low: F7 (1111 0111)

Sorry, haven't figured out what each binary bit stands for. Some need to be set and some "not set".