[outpaddling]

Apparently so, but I'm not sure exactly how yet. Can someone explain what the handshake combination is?

I bought my son a VEX kit over the holidays, and wrote a VEX loader for *nix shortly afterward.

I made a serendipitous discovery that Mac OS X and Linux trigger programming mode by accident when the port is closed. (FreeBSD does not.) This happens reliably with both the USB/serial adapter and with a direct connection to the serial port on Linux. I'm using the orange programming module that came with the EasyC kit.

I can prevent it from happening by dropping RTS using an ioctl() call before the port is closed. Apparently OS X and Linux drop RTS when the port is closed, and this is *part* of the handshake to trigger programming mode. I have tried various combinations of dropping and raising RTS and other control lines, with no success turning on programming mode.

Thanks,

Jason