FRAM NVRAM Board

EPROM EEPROM SRAM NVRAM Flash chips, reading/writing hardware and software
BennVenn
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Re: FRAM NVRAM Board

Post by BennVenn »

festy wrote:The VE numbers themselves aren't really important, and once you have 12P talking to your wideband you can work out the VEs pretty quickly by logging with an adx that includes CalcVE.
i.e.:
calcVE.jpg
That looks handy! Does the 'autotune' code modify VE or another individual table? The CalcVE feature runs on the logging software?

I've got the laptop with me today so I'll hopefully get 12p ready. I'll upload what I come up with if someone could look over it all?
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festy
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Re: FRAM NVRAM Board

Post by festy »

Yes autotune (VE learn) directly modifies the VE table if it's enabled, but calcVE is just a calculation done by the logging software (tuner pro) and recorded as an item in the log so it can be used without real-time hardware.
The VE learn doesn't differentiate between AE/DE and normal fueling so you really need to be aiming for steady cruising while it's enabled.
There's a bunch of parameters you can set to control how aggressive it is, and after getting the VE table in the right ballpark you probably want to disable VE learn and smooth out/fill in the gaps in the VE table by hand.
BennVenn
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Re: FRAM NVRAM Board

Post by BennVenn »

Odd that it isn't enabled under closed loop or cruise mode or equiv.
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Jayme
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Re: FRAM NVRAM Board

Post by Jayme »

yeah not many of us use it, mainly for the above reason, AE and DE can leave some incorrect spikes after a while in certain areas. I find tuning straight off the CalcVE in the monitor window is much quicker as I can pick out the cells I know are good data, edit those and smooth out the rest of the VE table to suit. it can get you 90% of the way to a good VE table on the first or second go.
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festy
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Re: FRAM NVRAM Board

Post by festy »

closed loop would only let you tune the areas the a narrow band and BLM would cover anyway.
BennVenn
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Re: FRAM NVRAM Board

Post by BennVenn »

Is BLM something all Delco's have? Or is that a 12P only feature?
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Jayme
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Re: FRAM NVRAM Board

Post by Jayme »

all delcos have BLM. it has 2 components, short term fuel trim (integrator) and long term fuel trim (blm). so the short term adjusts quickly to the narrowband o2, and if the short term trim is too far in one direction for a certain length of time, the BLM will increment in that direction and the integrator will back off a bit. the BLM table doesnt have as many cells as the VE table. each BLM cell covers a block of the VE table.
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pman92
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Re: FRAM NVRAM Board

Post by pman92 »

Loving this post! A massive credit to you being able to do everything you have. I'm actually jealous, wish I had the skill and knowledge to build my own ECU.

BLM is certainly in all the factory commodore code, not sure if pulsars etc had it but I assume they would of.
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Re: FRAM NVRAM Board

Post by BennVenn »

Cheers pman92, I enjoy learning new skills and actually applying them.

I'm about to disassemble the pulsar code now. Only 16kbytes!! haha
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antus
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Re: FRAM NVRAM Board

Post by antus »

Blm saves to ram too and is lost when you power off the 808 only has 256 bytes of ram (i think?) so its pretty low res.
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