RomRaider

Unless I've missed it I don't think this has been found.

Anyway, here is an example of how to change the baud rate of the logger. This is an AJ243, 2004 STI:

This should hold true for all the 512kb, 7055 based ECUs.
SMR is set to h'00 (cleared)
BRR is set to d'129

This results in 4800baud, 8-N-1, no "multiprocessor support", n=0

To know which channel, the same channel is set to 1200baud by setting SMR to #1 then BRR to d'129. I'm not positive it will be 100% consistent, but my ECU uses SCI channel 2. One other channel (SCI3) also has the BRR set to d'129, but SMR is also set to #1 which results in n:1, and 1200 baud. I'm unsure what that controls, but I did test changing it to d'64 with no immediately apparent ill effects.

The location is 0x3AE9E, 2byte.



To change the baud to 9600, the d'129 2byte 1D map needs to be changed to d'64.

The information on why and how this works can be found in the hardware manual.

If anyone wants to test a different 32bit DBW ECU other than the 2004 USDM STI (AJ243), please post a link to or post your ROM and I can give you a modified version to test. I'm not sure how to get Enguinity to let you log at 9600, as I don't use it to log at all, but Ecuedit just requires adding a small tag to be added in the XML for 9600 baud to make it a selection.

The effects are pretty apparent. Log period dropped on a particular set of parameters from 260ms to about 140ms. I added two extra parameters and only added about 10ms.

Very nice! Do you think this is supported on the 16bit ECUs as well?

This has been added for the next RomRaider logger release.

http://www.plasmatize.com/osecuroms/viewtopic.php?t=279

Theres link to my ROM. Would be more than happy to test? Are you using the Free version of EcuEdit or . .. . paid version?

This is huge. Nice find Freon

I would volunteer to test but it appears my ECU is the same as yours.

Tinywrex had a post a while back about finding the same thing in the 16bit ecus.

I also have an 04 sti.

Those with the 04 STI can test it as well, though it already works for me. With the AJ243, A2ZS710J just change 0x3AE9E from d'129 to d'64 and set your logger to 9600.

Jeramie:
A8JK100X: 0x4E67C should be it. Change it from d'129 to d'64.

I have not tried 14400 (d'42) or 19200 (d'32) baud, though that is perfectly possible as well. I'm only worried about sucking up CPU cycles. I imagine it isn't a big deal. 9600 is a good start. It can go up to 38400 (d'15).

Nice work Freon.

why only max at 9600 8-N-1, can we go higher? thats the limitation of the hardware? i'd like to get a copy of the assembly to do some eploration, where can i find this?

Very neat. I didn't realize the 32-bit ECUs had such a slow sample rate compared to the 16-bit, but I suppose moving twice as much data will do that..

We have the Evo SH7055 running at 62500 baud (4 times standard baud rate).

Yikes! Well the hardware document only lists up to 38400, although there is no necessary limit for the CPU to run other baud rates not listed explicitly. It describes the actual calculation used to convert the bit-rate register setting (the d'129, d'64 I'm talking about) to baud rate.

I'll probably try 19200, 28800, etc. over the next few days.

I'm hoping the speed increase will make road dyno calculations work far better if nothing else.

Just wanted to make sure there is currently no way to make the RomRaider logger support higher bauds right? (I realize it's not setup to now, just wanted to make sure, there is no easy XML edit to make this happen now). Thanks

It seems to me, with the crank position sensor giving goofy RPM readings at times, it might not be much better. MAF in g/s is a pretty good indication of power to the wheels and very consistant.