MJLJ Version 3.1.0

[brentp]

Version 3.1.0 of the MJLJ firmware will be available for beta testing very soon. After I give it a shake down I will expand the testing to any brave souls that wish to try it out.

Note that version 3.1.0 firmware will ONLY work with the later board designs- easily identifed by the green double-sided boards marked with V 3.0.0. Never fear- those with version 2.x boards will have a separate upgrade with many of the same enhancements.

Fixes:
- Fixed intermittent corrupt config data when reading data at high engine RPMs
- Improved RPM calculation stability

Enhancements:
- Serial API command ('u') to update a single ignition cell value- reduces update latency when tuning a running engine
- Serial API command ('V') to report version number
- Serial API command ('K') to update load axis calibration table- to correctly support TPS and support non-standard MAP sensors
- Ability to switch between Ignition configurations (via switch wired to OPTION port)
- Hysteresis on user outputs


A fix to the schematics will also be released.

- MAX232 correction

From the inception of the project, the MAX232 IC (U2) was incorrectly specified with 0.1uF capacitors. The capacitors affected are C3, C4, C5, C6.

The schematic will be updated to correctly specify a MAX232A, which is designed to work with the 0.1uF charge pump capacitors.

Evidently the capacitor mis-match has not shown up as a problem due to the relatively low baud rates (4800) between the PC host and controller.

For existing boards with MAX232 U2's can be easily patched by soldering 1uF capacitors in parallel with the existing 0.1uF capacitors, without needing to de-solder the existing capacitors.

[capri_turbo]

I have 1 question regarding uploading 2 maps as I really want to do this. Does the current tuning software support 2 maps? I'm guessing it must do. I'm probably being a bit dense here, but I'm guessing that to upload the second map to the MJLJ you would do so with the aux switch "switched on" while sending the map across?

[brentp]

Yes- Since it's hardware-switchable, it will be completely transparent to any software- depending on the position of the switch it will either behave one way or another.

[Tman]

Since im just about to biuld the unit and have bought a MAX232CPE+ ( I take it that will do the job ok? I compaired the data sheets and didnt seem to be much differance) Would it be a good idea to just replace C3, C4, C5, C6 with 1uF capacitors when soldering it up ? Or have i got the wrong end of the stick?
Cheers
Timon

[MartinM]

Yep, use 1uF for C3 - C6.

Again, make sure the 1uF physically fit (size and lead diameter) on the PCB

Note that there are other RS232 transceivers from other manufacturers that are designed to have 0.1uF charge pump capacitors.

[Tman]

Ok sorry to alter the direction of this tread, last question I promise.
Would 1.0UF 50V BLUE CHIP MONOLITHIC CAPACITORS be ok to use instead of the ceramic axial type? the local Jaycar has these avalible.
Thanks
Timon

[4600cc]

I have v2 board, and I wonder if it can be modified to run this firmware? i.e. so that it is same exact way as for v3 users.


Can I get communications part of the code? So I can upgrade the simulator.

What does the load axis calibration table looks like?



When you switch between ignition configurations, are you just switching ignition table, or the outputs, rev limiter, the whole thing? Whats hysterisys on user outputs?



Last, but not least, what about knock sensing?

[brentp]

Timon, yes- those capacitors should be fine.

regards,

[brentp]

Al,

- As I indicated in the main post, the V2 code will quickly follow the V3 code once the V3 code is released for general beta testing. So no worries there.

- I will provide the communications part of the code when it's ready.

- the load calibration table is the same 256 byte table currently represented by the KPAfactor table in the current firmware

- the whole ignition configuration changes- it will be transparent to the software. Hysteresis? simply look up it's definition.

- Knock sensing will be considered for a future release.

[4600cc]

The u function is a good thing. I have working prototype that allows runtime editing, and it is workable but is somewhat slow. Question, does u just updates or also writes flash?

[steve100]

Brent - does this firmware have the fix we discussed in early June to sense the timer overflowing and then set a default / configurable cranking timing of approx TDC or slightly ATDC advance setting?

Regards
Steve

[brentp]

However, I may not be able to make this configurable; however a fixed default value would be possible.

What default cranking advance would be ideal under conditions 'below idle'? 0 BTDC?

[steve100]

Yes 0 BTDC would be fine/perfect for most applications I can envisage.
I look forward to seeing how you code it in the source code.
Thanks for including that - vey much appreciated and I look forward to helping testing.
I like the new tuning software too inc the advance display and access via Windows icon!
Regards
Steve

[brentp]

Update on the 3.1.0 release:

I have the 3.1.0 code fully implemented with the following fixes and enhancements (mostly reflected from above)

Fixes (3.1.0)
- Fixed intermittent corrupt configuration data when reading data at high engine RPMs
- Improved RPM calculation stability

Enhancements:

- Dual Ignition config support, hardware switchable (via 'option port') at runtime.
- Update single ignition cell support- to dramatically enhance PC app -> controller communication performance while tuning.
- Firmware version number reporting
- Full TPS / Alternate MAP sensor calibration support. Finally: after calibration, TPS will measure real throttle opening percentage. External MAP sensors will also be possible.
- Hysteresis on all configurable outputs
- Cranking RPM will default to ignition cell (0,0). This is special behavior for those that need a specific ignition advance while cranking. (For reference: Cranking RPM occurs when RPM is below 457 RPM)
- Runtime state command extended to indicate user defined output states, plus which ignition configuration is currently active.

2.x firmware

Good news: I will release the new 2.x firmware simultaneously with the 3.1.0 release. Same set of features as above.


For those of you ready and willing to beta test- especially those of you who have set up an EDIS test bench (I know you're out there!!) I would appreciate your time testing this new firmware. I have simulated it on a test bench, but not yet on a running engine (race car is parked for the winter).

I'm excited to release these enhancements! They will add significant value to your investment, and best of all, they will work on your existing controller (some small hardware mods for dual ignition config may be necessary- more on that later)

I should have the files and documentation available by this weekend.

[steve100]

Brent - can't wait - I'm ready & raring to go - and have my bench tester waiting !!!

Thanks for doing these enhancements.

Looking forward to trying to update the firmware successfully from my PC!!

Regards
Steve