New JimStim firmware V2.0
Posted: Wed Apr 22, 2009 2:28 am
I have posted what follows on the msextra forum (http://www.msextra.com/viewtopic.php?f=102&t=31012) but I thought this might be of interest to people here. Of particular interest to some may be the new 360 tooth CAS patterns.
There is a new firmware available for the JimStim CPU. This V2.0 firmware will now be provided with all the new JimStim boards and kits (the JimStim board is still the V1.4) and it is compatible with all JimStim board versions.
This new firmware includes more wheel modes than before (42 modes now) and one of the invert switches has been converted to be used as an additional mode selection switch. So now, DIP switches 2 to 7 are used for wheel mode selection which allows up to 60 wheel modes to be selected through the switches (the 4 modes which have switches 3 to 6 set to "on" are either reserved or invalid). The single remaining invert switch now invert both the primary and secondary tach signals together. The wheel modes correspond to what is currently available in the MS2/Extra code as described here. In addition to the new wheel modes, the clock speed has been increased which makes all wheel modes perform more consistently and at a higher RPM limit.
The new firmware now makes full use of the serial communication capability available on the JimStim board. It is now possible to remotely configure the JimStim from a PC by using either Megatune or TunerStudio. TunerStudio is the preferred interface since there are limitations in Megatune that prevent the selection of all the wheel modes (at least directly by name). What can be configured on the PC are the wheel mode, the tach signal polarity (primary and secondary tach signal polarities can be set independently as opposed to what can be done using the DIP switches), the RPM, and the communication baud rate. One side benefit of this is that the RPM is now only limited by what the CPU can handle and is not artificially limited to about 16500 RPM by the RPM pots. The actual limit depends on the wheel mode and can be from about 4000 RPM (with the 360 tooth CAS modes) to more than 50000 RPM (with the EDIS mode).
Another new feature, is the possibility of upgrading the wheel patterns without having to change the code. There is now a small utility that takes a text file (which uses a pre-defined format) and converts it into the binary data and then sends this data to the CPU. The default wheel patterns can be modified, removed, or moved and new patterns can be created. There can be up to 240 wheel modes in theory but the actual limitation becomes the available memory. However, the wheel patterns can be changed as often as desired so unless someone needs to work with a lot of big patterns at the same time, the memory limitation is not a big problem.
The last new feature is the possibility of having a dynamic RPM control. The V2.0 firmware has a command that allows new RPM values to be sent as fast as the serial port will allow and the generated tach signal will be adjusted accordingly. This allows the creation of RPM patterns for bench testing different ECU functions. There is a small example program provided on the web site that uses this feature to vary the RPM from 1000 RPM to 12000 RPM and back down to 1000 RPM. The source code is provided and can be used as a basis to generate more patterns. Hopefully this feature will be integrated in some way in a future release of TunerStudio (thanks Phil ).
For more information, you can have a look at the V2.0 firmware web page.
Jean
There is a new firmware available for the JimStim CPU. This V2.0 firmware will now be provided with all the new JimStim boards and kits (the JimStim board is still the V1.4) and it is compatible with all JimStim board versions.
This new firmware includes more wheel modes than before (42 modes now) and one of the invert switches has been converted to be used as an additional mode selection switch. So now, DIP switches 2 to 7 are used for wheel mode selection which allows up to 60 wheel modes to be selected through the switches (the 4 modes which have switches 3 to 6 set to "on" are either reserved or invalid). The single remaining invert switch now invert both the primary and secondary tach signals together. The wheel modes correspond to what is currently available in the MS2/Extra code as described here. In addition to the new wheel modes, the clock speed has been increased which makes all wheel modes perform more consistently and at a higher RPM limit.
The new firmware now makes full use of the serial communication capability available on the JimStim board. It is now possible to remotely configure the JimStim from a PC by using either Megatune or TunerStudio. TunerStudio is the preferred interface since there are limitations in Megatune that prevent the selection of all the wheel modes (at least directly by name). What can be configured on the PC are the wheel mode, the tach signal polarity (primary and secondary tach signal polarities can be set independently as opposed to what can be done using the DIP switches), the RPM, and the communication baud rate. One side benefit of this is that the RPM is now only limited by what the CPU can handle and is not artificially limited to about 16500 RPM by the RPM pots. The actual limit depends on the wheel mode and can be from about 4000 RPM (with the 360 tooth CAS modes) to more than 50000 RPM (with the EDIS mode).
Another new feature, is the possibility of upgrading the wheel patterns without having to change the code. There is now a small utility that takes a text file (which uses a pre-defined format) and converts it into the binary data and then sends this data to the CPU. The default wheel patterns can be modified, removed, or moved and new patterns can be created. There can be up to 240 wheel modes in theory but the actual limitation becomes the available memory. However, the wheel patterns can be changed as often as desired so unless someone needs to work with a lot of big patterns at the same time, the memory limitation is not a big problem.
The last new feature is the possibility of having a dynamic RPM control. The V2.0 firmware has a command that allows new RPM values to be sent as fast as the serial port will allow and the generated tach signal will be adjusted accordingly. This allows the creation of RPM patterns for bench testing different ECU functions. There is a small example program provided on the web site that uses this feature to vary the RPM from 1000 RPM to 12000 RPM and back down to 1000 RPM. The source code is provided and can be used as a basis to generate more patterns. Hopefully this feature will be integrated in some way in a future release of TunerStudio (thanks Phil ).
For more information, you can have a look at the V2.0 firmware web page.
Jean