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TD5 Speedo Mileage run up circuit


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Top idea, I'd donate for that.

Although I expect Mr Wabbit could become a very busy man, and would reasonably like something for his efforts too.

That may be a good way to get more example flash dumps to help work out what the other contents are. At the moment I'd guess it would take about an hour to do the dismantling, soldering, reprogramming and reassembly... with the proviso we haven't actually put James's back together yet! :)

How much of a forum donation would that be worthy of? I don't mind doing them for free providing any expense is covered (probably just return postage, can't think of owt else) and people understand no guarantees are provided. Also I reserve the right to change my mind if it turns out 1000's of people want them redone and I'm not getting any sleep! :P

All information discovered about these Speedos will be published on LR4x4 so people are free to just reprogram their own if they like.

Important point to note at the moment is there are some marks left on the back of the metal ring that holds the glass in place using our current method. These are not visible when it's put back in the binnacle though.

Edited by CwazyWabbit
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Hell, I go away for a day and change a steering box and we make some right progress. Would be real good if we could make something to talk to the 3 pin port on the back to avoid opening the case.

I manage with this electronics stuff but dont get a great deal of time to use it. Id be interested in making a micro controller based LCD display / button arrangement to type a new mileage in to adjust the mileage from out side the case but have no idea how that port works.

Great work, today we have covered some ground..... : )

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..... Would be real good if we could make something to talk to the 3 pin port on the back to avoid opening the case.

I manage with this electronics stuff but dont get a great deal of time to use it. Id be interested in making a micro controller based LCD display / button arrangement to type a new mileage in to adjust the mileage from out side the case but have no idea how that port works.

...

Good point, would make changing them a lot quicker, which has to be a good thing. :)

So far all I know about that 3 pin port is

Centre pin is GND

The other two pins are connected to the main chip via resistors.

There has been no observed activity on the pins during testing apart from one being pulled to 5v at power up.

We have been unable to find the main chips datasheet....yet.

We have anecdotal evidence that to reduce mileage requires opening the case but adding mileage can be done without opening the case.

I have clocked the input on this speedo at approx 1.6khz with no adverse affects observed, mileage increased at approximately 25 miles per minute. Any greater frequency and the speedo fails to register a signal. Even so that is about 1500MPH which means you could add 50 000 miles to a speedo in about a day and a half, using a microcontroller You could automate the stop time so you don't overshoot.

It has so far been a good day :)

Edited by CwazyWabbit
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As mentioned before, the Buspirate is exactly the widget to communicate with this, cheap, open-source, off-the-shelf and works on anything with a USB port (and has 100's of other uses too - anyone for CANBUS?)

Very good point, and it looks like it has microwire support already if people want to program their own flash :)

http://code.google.com/p/the-bus-pirate/source/browse/trunk/scripts/pyBusPirateLite/MicroWire.py?spec=svn355&r=355

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Unless Digidash just used a drill on Ralphs!

it would still be there having 300,000 miles added :P

when the total milieage reading reaches 100,000 the decimal point moves to the trip mileage, simply because there isn't enough display space on the total mileage line for 7 or 8 digits.

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Is that a warning light in the middle of the dial, just above the needle pivot? Can you tell I've never seen a TD5 speedo? :)

If it is, I wonder if it's a speed warning light. I think some markets (Japan?) have overspeed warning lights at 120kmh. Maybe one of the bits toggles this? My first guess would be word 10 (currently 8000, only one bit set)

Rob.

it's a red led for the LR alarm/immobiliser system fitted to Td5 Defenders, it lights when ign is off & alarm unit earth the led to illuminate/flash it as a 'armed' warning.

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Out of curiosity Ralph how long did they take to add that much?

if you mean how long in driving, I've had my 110 for 18 years this July, had 73,421 on when I bought it.

it was with Digidash for 1 day & that includes travelling time with Royal Mail to & from my home in Cornwall to East Sussex

I gave up trying to increase with the drill running the transducer, just taking far to long, was quicker & less wearing on me to send it to someone who knew what they were doing.

excellent thread :D but you lost me when talking FFFF FFFF et all :wacko:

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Good point, would make changing them a lot quicker, which has to be a good thing. :)

So far all I know about that 3 pin port is

Centre pin is GND

The other two pins are connected to the main chip via resistors.

There has been no observed activity on the pins during testing apart from one being pulled to 5v at power up.

We have been unable to find the main chips datasheet....yet.

We have anecdotal evidence that to reduce mileage requires opening the case but adding mileage can be done without opening the case.

I have clocked the input on this speedo at approx 1.6khz with no adverse affects observed, mileage increased at approximately 25 miles per minute. Any greater frequency and the speedo fails to register a signal. Even so that is about 1500MPH which means you could add 50 000 miles to a speedo in about a day and a half, using a microcontroller You could automate the stop time so you don't overshoot.

It has so far been a good day :)

I still think that Western's Speedo must of been opened up like mine to change. Maybe he did a better job of resealing and crimping the ring back down?

Though i do think you're doing a great job on this!!

Chris

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I still think that Western's Speedo must of been opened up like mine to change. Maybe he did a better job of resealing and crimping the ring back down?

Though i do think you're doing a great job on this!!

Chris

I'll take it out of the truck over the weekend & have a good look, it didn't look tampered with when I got it back.

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Would be worth tracing the connections from the 3 pin connector to the relevant chip to see what inputs they are connected to (not easy on 3-4 layer pcbs!!!) , then grabbing the datasheet of the relevant chip and what level they operate at. If there is a xtal, worth checking what frequency it is operating at. (and be careful of cheap meters as the buzzer could potentially blow the low voltage circuits, probably stating the obvious now!)

Great work guys, keep it up !

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Would be worth tracing the connections from the 3 pin connector to the relevant chip to see what inputs they are connected to (not easy on 3-4 layer pcbs!!!) , then grabbing the datasheet of the relevant chip and what level they operate at. If there is a xtal, worth checking what frequency it is operating at. (and be careful of cheap meters as the buzzer could potentially blow the low voltage circuits, probably stating the obvious now!)

Great work guys, keep it up !

Middle pin goes direct to GND and the two others go via resistors to the only other chip on the board besides the eeprom. Unfortunately the IC manufacturer seems to be quite good at keeping their datasheets secret.

The chip in question is a Micronas CDVN 2117, there's a picture somewhere on page 2

I'll take a look at the Xtal in a mo...

I'm thinking a few more examples of flash contents might be helpful now..... any volunteers? ;)

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I'll take it out of the truck over the weekend & have a good look, it didn't look tampered with when I got it back.

That would be great Ralph, there may be a few marks on the white plastic and the inner edge of the metal ring if digidash opened yours. Although I imagine they are quite practiced at it now so the marks may not be too obvious.

Thanks again :D

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I've been following this thread with interests as I'm planning on doing the panel conversion. You guys lost me extremely early on (I only just learnt about hex)and am extremely impressed at your abilities.

"I'm thinking a few more examples of flash contents might be helpful now..... any volunteers?"

Even this gets me :blink: - If it means you want another speedo to try, I have one waiting in my garage with unknown mileage on.

Malcolm

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I've been following this thread with interests as I'm planning on doing the panel conversion. You guys lost me extremely early on (I only just learnt about hex)and am extremely impressed at your abilities.

"I'm thinking a few more examples of flash contents might be helpful now..... any volunteers?"

Even this gets me :blink: - If it means you want another speedo to try, I have one waiting in my garage with unknown mileage on.

Malcolm

The memory chip inside the speedo that stores the mileage when the power is off is a type of memory chip known as a flash memory chip. Flash contents is just shorthand for contents of the flash memory chip. By comparing the information in these chips we may be able to work out what else is stored there.

Where abouts are you located Malcolm?

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Got a speedo you can have a look at !

Just been on the micronas website and found a uk distributor, I'll send an enquiry from my prof. email tomorrow !

Fingers crossed you get a result with the enquiry, they may tell you it's obsolete though (I don't know if it is) and try to sell you something else, but definitely worth a try :D Even a datasheet for a related chip may be of use....

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I'll take it out of the truck over the weekend & have a good look, it didn't look tampered with when I got it back.

I got mine changed a couple months ago by a guy in a mobile van. He pointed out to me some damage around the case crimping to say that it had been opened before and wasn't him. Afterwards, he said it was as difficult to open as a motorcycle speedo... :huh: So in my case, it was definitely opened.

I tried the drill too but calculated it would take a week at full tilt, keeping the drill piece perfectly in line and soundproofing it from the neighbours. Ended up paying £70 to this guy after quotes of up to £230! And he did it in 20 minutes.

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I got mine changed a couple months ago by a guy in a mobile van. He pointed out to me some damage around the case crimping to say that it had been opened before and wasn't him. Afterwards, he said it was as difficult to open as a motorcycle speedo... :huh: So in my case, it was definitely opened.

I tried the drill too but calculated it would take a week at full tilt, keeping the drill piece perfectly in line and soundproofing it from the neighbours. Ended up paying £70 to this guy after quotes of up to £230! And he did it in 20 minutes.

I think most cars are easy to open the instruments on, I have a ford galaxy instrument pack here and just a few screws and it's all in bits.... although I think it's mileage is stored in the ECU.

Just for info, was he adding miles on or taking them off?

Cheers for the information :)

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