freeSim: Firmware

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ababkin
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freeSim: Firmware

Post by ababkin »

[last updated Feb 17, 2008]

freeeSim: Firmware

!!! Please dont post in this thread !!!
... but please feel free to discuss freeeSim firmware here: http://www.diyefi.org/forum/viewtopic.php?f=4&t=61

The purpose of this thread is to document the firmware side of the freeeSim.
see the original freeeSim 'big-idea' thread here: http://www.diyefi.org/forum/viewtopic.p ... p=190#p190


Below, the functionality of firmware is presented in reasonably abstract manner.

Time-critical outputs:

Tach outputs (crank and cam):
Tach outputs are required to set the tach signals in accord to the current RPM value, as close to a real crank/cam wheels as possible. (test with oscilloscope)
Several programmable wheel patterns will be available, which will be possible to set with the freeeSim software.
A protocol of continuous-only change in real-time RPM between freeeEMS software and hardware interface to the EMS will have to be developed, to implicitly avoid a physically implausible case of instant change in RPM (i.e inertial must always be present in the reciprocating mass of the simulated engine). As an example of such a protocol, instead of setting the RPM value directly, the software would pass the rate of change of the RPM in respect to time (potentially in variety of orders, i.e linear factor, quadratic factor, etc)

[to be continued...]
Last edited by ababkin on Wed May 14, 2008 2:23 am, edited 2 times in total.
Legal disclaimer for all my posts: I'm not responsible for anything, you are responsible for everything. This is an open and free world with no strings attached.
User avatar
ababkin
LQFP112 - Up with the play
Posts: 215
Joined: Tue Jan 15, 2008 5:14 pm

Re: freeSim: Firmware

Post by ababkin »

freeeSim sourceforge.net project is up!

http://sourceforge.net/projects/freeesim
the code had been GPL'ed and available in the svn repository.

brief firmware status:
- uart works (can use printf for output and poll the ringbuffer for incoming data)
- spi works
- interface specific to the MCP23s08 works over SPI
- 60-2 tach wheel simulation works
- events capture (hardware interrupts on inj/ign signals) works and logs (through uart to a PC) in relation to the angular position of the imaginary tach wheel

coming soon:
- software front-end to visualize the events with reference to a crank angle set by the tach wheel
- DAC/digipots+capture-and-hold circuit+opamps and firm/software functionality update to simulate analog outputs for signals like MAP, WBO2, MAT, CLT, etc
Legal disclaimer for all my posts: I'm not responsible for anything, you are responsible for everything. This is an open and free world with no strings attached.
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