Bit rate between the Motec M800 & the Computer

[nick.ashwa]

We've been using the motec M800 and were trying to get a wireless interface between the computer and the motec thereby saving the need to plug the CAN cable all the time. Does anyone have any idea on the bit-rates of the CAN or RS-232 interface between the motec and the computer?

[MarkMc]

Hi Nick,
The CAN bus works at 1Mbps. You can only talk to the ECU via CAN but obviously you can use the UTC (USB to CAN adaptor), you cannot us the RS232 to talk to the ECU.

The problem you may have is the wireless communications no matter how you do it. The communications to the ECU for tuning and configuration purposes MUST be very robust, the software has a very low tolerance to lost packets of data.

[Martin]

Hi Mark,

This low tolerance is so low that in some cases you cannot change large portions of the map with the engine running without having problems. This happens if you use a long USB cable.

Could this tolerance be lifted?

[nick.ashwa]

Hi Mark,

We were thinking of using a Zigbee controller which has a bit-rate of 500kbps, and 1.2% error probability. Could we use the USB end of the CAN-USB converter to interface it between the system. Its more or less like putting a wireless link instead of the USB wire we conventionally use.

The motec M800 does have a provision of communications with the RS232 interface, could we use that in any way to set a link up??

Regards,
Nick.