LAOS Laser

I expect that there is something wrong with the I2C connection. Please check the connections and see if R7 and R8 on the mainboard are correct.
Also check the routing of the cable, not next to motor wires; the ground and 5V wire should be next to the SDA and SCL along the whole path.
If possible monitor the 5V wire with an oscilloscope or a multimeter to make sure it is a solid 5V all the time.

An 128MB SD card is fine. Note that on the rev5 board you need to use a normal size SD card holder or if you're using the micro sd holder you need to apply a patch.

thanks
i eventually realised that the problem lay with the atmega 328 chip i was using or at least the firmware.
when I originally had difficluty in reprogramming my 168 chip, i purchased the 328 thinking it was compatible. I must have gone wrong somewhere along the line as it behaves strangely when in use but not when testing.

now I have (at last!) got my original chip reprogrammed all seems well.

When using the arduino software using a usb to ttl link, i set the board to ng or older but the chip options do not show an atmega 328 option, (only 168 or 8). but it lets me still upload the firmware ok. I don't know if this was the problem or not?
Anyway I'm happpy as all appears good!

thanks again