I use a datalogger and dash from the company Race Technology.
Race Technology sold the display with what they name "Vems interface", without testing. Unfortunately it does not work.
Protocol details
- VEMS firmware sends data via [AIM protocol],
- the scalers were made according to [AIM-protocol.pdf] with only minor corrections to match the Race-Tech Motec interface (which was found to deviate slightly from the protocol.pdf, eg wheelspeed 10x multiplier).
Other channels:
Example of data streamed from my v3:
http://www.vems.hu/files/HankMoody/aim-new%20hypertrm.TXT
It seems there are more channels streaming from my v3! I also see activity on channels 224-229 in my data. What are theese channels used for?
- 224-229 are AIM_OUT_0 .. AIM_OUT_5, custom outputs
- eg. boostcontrol solenoid output channel, idle solenoid output channel can be actuated by other device, say, round if configured so (very useful on V8 where ++ number of outputs help)
- .. channel=Xe where (X=0..5)
- disable outputs by i7, not by i6 (unless you know what you are doing)
- we'll review your vemscfg in this respect
- however any AIM receivers just neglect the channels they don't know. Chance is 0.00% that disabling 224-229 will get Race-Tech working if it does not work with 224-229 transmitted.
Im running v3 firmware 1.1.96
Some of the channels within the AIM datasream are correct.
- TPS displayed good (AIM channel 45)
- RPM (sent by VEMS in AIM channel 1). Examples sniffed in hex from terminal - shows vems firmware sends correctly:
- (03EB=) 1003RPM - 01 A3 03 EB 92
- (07D6=) 2006RPM - 01 A3 07 D6 81
- [VEMS-ecu interface]
- it says "Note: AIM protocol used" but it obviously is not using the [AIM - RS232 protocol] that v3 properly sends (when enabled)
- it also says conflicting info at the same place: "The VEMS ECU outputs 56 byte sequence of data at 19200bps baud rate." - this suggests the Race-Tech display does NOT actually use AIM, but relies on the 'A' command that old firmwares (before 1.1.96) used for sending real-time data to VemsTune and megatune. (offsets found in global.h and megatune.ini, and everyone knows runtime data sending works, but for longterm compatibility AIM-RS232 is a much better choice to rely on).
- new v3 firmwares (eg. 1.2.x) only act on CRC-protected commands ("triggerframe protocol") to prevent corruption (due to serial noise). In other words it does NOT reply at all on non-CRC-protected commands like the 'A' command.
- if someone reports that his RaceTech works with old (pre 1.1.96) firmware (AFAIK not, but maybe with new Race-Tech firmware... who knows) but not with v3 / 1.2.x, we can help him this way: we offer to work out a v3 config bit to "enable unprotected communication for A-command", that would answer maybe after AAA, to make it easier for RaceTech
- Sometimes (very random) I can get some of the channels working, but only when the AIM-signal is turned OFF in the v3. (v3 firmware definitely does not start to send out the AIM signal after boot when AIM is disabled in config)
- that suggests Race-Tech is not using AIM, but querying via 'A' command ?