Program/Use "Microcontroller" via direct USB connection about hax

[jmesmon]

"Search" (on the VEXNet update program) appears to send a usb control message with the following fields:

• request = 09h (HID SetReport)
• value = 0200h
• index = 0h
• data : 63 bytes of FFh followed by 1 byte of 28h or 40h. 40h is sent to MC, 28h to OI.

Championship 2010 Firmware:
This causes the device to alter its interrupt transfer so that the 0x3C and 0x3D bytes in that trans fer change from 00 00 to 02 04 (in the current case I'm testing, MC coms)

Firmware 2.3:
No change seen following command.

The same command is sent to both OI and MC.

[brycelelbach]

EasyC can also program through the direct USB link (EasyC for Cortex). I'm attaching USB-sniffer logs taken during the download of the default EasyC firmware onto a Cortex chip.

[brycelelbach]

Hm, can't seem to attach it on github. Message me if you're interested in the logs.

[jmesmon]

I am. Very interested.

[brycelelbach]

This is now doable with the latest LPC firmware, at least on Windows. I haven't thrown together a Linux driver yet. First, flash the Cortex to the latest firmware, and install the VeXNET serial driver for Windows from the VeX site. Then, put the Cortex into config mode, and plug it into your machine with any usb-to-usb cable. With the new driver, the Cortex now shows up as a USB CDC device instead of a USB HID device. The VeX windows driver emulates a COM port for it, and this can be used with utilities like stm32flash. On Linux, I haven't found a driver that does the emulation properly yet, but USB CDC is much eaasier to work with than USB HID.

[jmesmon]

Hey, i took a look at the "VeXNET serial driver" when it initially came out. All it does is tell windows to use the standard usbserial driver, so all that is needed on linux is to add the vid/pid to a list in the kernel.

[brycelelbach]

nods

It's a little tricker than that - I tried doing that, but the input and output lines are reversed from the Linux defaults. I still need to do some more research here.

[jmesmon]

Could you clarify what you mean by "the input and output lines are reversed from the Linux defaults"?