I had the same problem. turns out some pins were connected to ground when they shouldn't have been. I don't really understand the problem, but it works fine now.

Hi,

I am running XP and I can not load new programs onto meggyjr. The unit just
resets. I dealt with the RTS issue and hit the reset button several times. I would
like to reprogram the chip using the USBTINYISP. Could you please give me specific instructions on how to do this.

> I would like to reprogram the chip using the USBTINYISP.

I presume that you mean just to reflash the bootloader so that you can thereafter use the USB-TTL cable. (If you mean to do all future programming through the USBtiny, *instead* of the USB-TTL cable, please say so.)

Turn off power to the Meggy Jr RGB.

Plug in the 6-pin connector of the USBtinyISP to the 6-pin (2x3) ISP connector on the back of the Meggy Jr RGB. The Meggy Jr RGB circuit board and case have a little arrow to mark pin 1 of the connector. Make sure that pin 1 of the connector from the USBtinyISP goes that way, not 180 degrees off. Pin 1 usually marked by (a) an arrow on the connector, (b) a single stripe on ONE END of the ribbon cable to label that as the end with pin 1, or (c) an embossed manufacturer's name on the connector, which works something like an arrow to label pin 1.

If your USBtinyISP DOES NOT have the power jumper installed, turn on the power to the Meggy Jr. Otherwise, it should be powered already and you SHOULD NOT turn the power on from a different source at the same time.

Open the Arduino IDE. Select the correct board from the menu (Arduino Duemilanove "with 168" or "with 328", depending on which you have), and then select the menu option Tools> Burn Bootloader> W/ USBtinyISP.