SIMON HOLTBY

Just interested if anyone else is loading 2 bins on a 256k chip and changeing between the 2 by switching between 0v and vcc on A14 pin 27 I think it was.
eg race and cruise/economy bin

new test bin and reliable bin

love you all

Simon

Craig Moates

Yep, works grrreat! I used a 10k resistor as a pull-down off the Vcc, so the NO switch gives me +5v at the address line and upon closure it's at ground state.

Kinda works on-the-fly, but the ECM stumbles a little probably due to switch bounce. I was just using a 0.1" jumper.

SIMON HOLTBY

Hello Craig,

I dont hear of many others using this method. I'd have thought Grumpy and others would find it useful to have a race and street bin on one chip and a remote switch to change between. At the moment they must be swopping memcals
How do you do your switching? Have you modified the main circuit board in the ecu or the memcal?
While I have your attention is it possible in a future version of your scan software to show MAF voltage rather than airflow. I think this would make tunning simpler as if you found at a given MAF voltage the mixture was wrong you could go to the MAF tables and alter the value for that voltage. At the moment you are told the airfow then you have to find the voltage and alter the airflow value.
Found a major problem with my propane prom as I have most of the MAF values set to zero the ecu does not see any load on the engine so the timing is way advanced. Hence my spark table only varies with rpm so I have to use conservative values. It still drives well though and I'm getting 20 mpg which with propane half price is great.
There was an american car show close to where I live today some good cars there. Although I think most of the saloon cars are big and rather ugly I like the corvettes mach 1 mustangs and 2, 3 and 4 th gen f bodies. Still have not seen anything I'd swop mine for though. A friend is getting a 1990 BMW M5 soon I hope I'm not tempted to buy it as he doesnt keep his cars long. It will I'm sure be great but I have had german cars before and parts and insurance costs are extortionate.

Cheers

Simon

junkcltr

iTrader: (1)

Craig,
The switched must be de-bounced and look at CS for on the fly switching.

J

Craig Moates

Hmm,

Don't think the MAF voltage is available directly in the standard 165 stream. No reason it can't be mapped there though, but that would require some more advanced BIN patching...

The switch I was using is real straightforward, just a pulldown resistor (10k) coming off the Vcc +5v supply with a ground path at the address line which is switched.

Debounce with rising-edge sync off of a D-Flipflop I think is the way to go too. Just put a logic gate in front of it and you should be in good shape. Still haven't put one together, but I think I have in mind what will work. Still planning on putting a switcher into production which will allow 16-channels of on-the-fly selection using quad D-Flipflop (74HC175 looks to be ideal). Just need to figure a way to tie the rising-edge chip request (to clk) in with a 'select' button for ANDing the event to allow update exertion of the selected bits at the address lines ONLY when the edge comes AND the select button is pressed...