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Watched the great videos and was interested in the drone cars. I can understand one but not entirely sure how you get more than one with only a single controller. I like the idea of racing in and out of traffic when I am 'Billy no mates'!

I would buy the first Scalextric Digital set I saw if there was a genuine pace car function however.
 

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QUOTE If the chips are identical in functionality with the only difference being physical size, I cannot see any sense in making the larger one. Why bother with it?

Economics. Manufacturer's look to keep costs down. If the smaller chip is more expensive to manufacture (and less reliable) then economically it may make sense to produce two chips: one for general use and the more expensive chip for specialized use in cases where the cheaper chip will not work (ie formula 1 cars).

Steve
 

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Very interesting new videos.

Lots of the anti-digital camp have been commenting on how shunts will lead to offs - well there are a lot of shunts in these videos, and they are not resulting in the cars crashing!
 

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QUOTE (fouldsc @ 25 Oct 2004, 15:41)Now the controllers are sending digital signals to the base station instead of
applying resistance in the circuit we have something that we can record.
If we take the digital signals and pass them through a voltage to frequency
recorded you can feed that into your PC as a simple WAV file.
Then play it out again via frequency to voltage converter and you replaying
laps.

<{POST_SNAPBACK}>

...or map the data to synthesized engine sounds while you race...

...or analyze the signal and work out Scalextric's data protocols so that 3rd parties can start making lap counters that you can actually SEE whilst racing.

We need some serious tech heads to connect a packet sniffer to this thing and kick start the beginings of open-source Scalextric Digital, since I am not at all hopeful that any of the manufacturers will release technical information to the public.
 

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QUOTE (SinclairZX81 @ 7 Nov 2004, 04:52)...or map the data to synthesized engine sounds while you race...

...or analyze the signal and work out Scalextric's data protocols so that 3rd parties can start making lap counters that you can actually SEE whilst racing.

We need some serious tech heads to connect a packet sniffer to this thing and kick start the beginings of open-source Scalextric Digital, since I am not at all hopeful that any of the manufacturers will release technical information to the public.

Your right , soon as you a sample of the protocol from the handset to the base
you can do alot of things.
As far as I can tell they will be three types of message , brake , change lane and
a throttle message with a variable (i.e. amount of throttle) - should be easy to map.

The lap counting , ermmm - not so sure how easy that going to be as thats worked
out by the base station and not fed out anywhere.
Need to put thinking cap on over that one.
 

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Guys

Video is great. Fantastic job....

Can any one answer me the following questions

Will the challanger be able to run on the digital setup after have a digi chip added ?

Will this still be operated by the control tower or by the digital station ?

Will the challanger car be able to change lanes ? (This would be very cool).

If i understand digital right two challanger cars could be run at once with different ID's more to race against.

Hope some one can help me

Thanks

ScalextricRacer
 

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QUOTE (astro @ 13 Nov 2004, 22:34)Scalextric Challenger CANNOT run on a digital system. The videos are of challenger 'style' racing, I think they have wodged a controller to give a fixed speed or something.
<{POST_SNAPBACK}>

Yeah, they used a 'wire tie', it says it right there on the review site.

It would be trivial for Scalextric to add the ability for one or more cars to behave as Challenger cars however. Giving them the logic to lane change intelligently would be trickier if not impossible, as I don't think the system has any idea of where each car is on the circuit. I think this would require 2-way communication... which makes me wonder, how do they handle data transmission errors? I guess they just ignore them since another 'packet' will be coming along anyway, but I wonder if a request to brake (say) might ever get 'lost'.
 

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QUOTE (SinclairZX81 @ 13 Nov 2004, 23:31)I wonder if a request to brake (say) might ever get 'lost'.
<{POST_SNAPBACK}>
i don't think the controller is supposed to send once only messgaes. If you stab the brake, you are probably holding it for 1/10 second or something, which hopefully is time for 10 or 100 messages, depending on the systemes frequencey. Even if 15% of the messages get lost, you will end up braking for about 1/10th of a second, or at least from the time of the first succesful 'brake' message to the first succesful 'don't brake' message. (big error percentages are most likely to lead to a sluggish response and a feeling of delayed response)

Similarly with lane changes, you hold the button down until the lane is changed, it is not a click once operation.

This should apply in theory to all the digital systems, not just scalextric.
 

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I agree with jnr seahorse.

The videos are fantastic and give a lot of food for thought.
I can understand how a contoller could be set to run one 'drone ' car ( a tie is mentioned ) but dont understand how more than one could be done.
It does say on the notes for one of the videos that " due to the design of S.Digital setting a controller to run up to 5 cars does not generate heat in the controller "

Anyone who did the video care to elaborate exactly how the controller is/was set up to cope with 5 cars?

Personally I cant wait for this - Digital is going to be great for the home racer. That is of course providing there is a reasonable amount of space for a decent size layout - not something everyone has.
 

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While waiting for the guys who did the video to respond...each car has a "receiver" looking for a certain frequency. When it hears its frequency it does what it is told...like having five portable radios in the same room on the same station.

The hand controller does not handle the voltage, the box does. The same voltage is sent all the time roughly while the signal to the car tells a device in the car how much voltage to allow through to the motor...thus speed control.

...I now await a well-rounded correction from Tropi or Astro which I probably deserve.


 

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QUOTE (Maltese @ 14 Nov 2004, 02:26)While waiting for the guys who did the video to respond...each car has a "receiver" looking for a certain frequency. When it hears its frequency it does what it is told...like having five portable radios in the same room on the same station.

The hand controller does not handle the voltage, the box does. The same voltage is sent all the time roughly while the signal to the car tells a device in the car how much voltage to allow through to the motor...thus speed control.

...I now await a well-rounded correction from Tropi or Astro which I probably deserve.



<{POST_SNAPBACK}>

Its a pretty good explanation. The radio analogy works... but you guys are like... so analog


Each car has an numeric ID corresponding to a controller (your 'frequency' above) You assign a car an ID at the start of the race.

Data is sent along the track in 'packets' and each car keeps checking each packet, disregarding any that are not 'addressed' to it. When it receives a packet that is addressed to it it reads the data in that packet. I imagine the packets are pretty simple and pretty small since the ID can only range from 1 - 6 (0 - 110 binary, only 3 bits needed there!) and there are only.. what, 3 opcodes : change speed, brake, change lane. Each of those opcodes will also be a number (cos that's all computers understand kiddies!), so lets say in our imaginary system change speed is 01, brake is 10 and change lane is 11.

In such a system a typical packet would look like this:

0001 0001 1000 0000

So from left ot right this packet says

0001 This is addressed to car number 1
0001 Command is accelerate/decelerate, next byte contains value...
1000 0000 Speed value is 128

I am not saying the Scalextric system is this, this is an imaginary over-simplified explanation, there will definately be more overhead in each packet in a real system (like a checksum so the car can ignore damaged packets) and speed may be expressed in 2 bytes etc. The more bytes used the finer the control.

Astro is right that the system will keep sending the message until the message changes basically, nevertheless its theorectically possible that all your brake messages could 'screw up'.. just extremely unlikely. Still, I think its inevitable that sometimes 'weird ****e' will happend, just as it does with CD's and DVD's and computer programs. Of course analog has its own 'weird ****e', just like static of old was replaced by pixel artifacts, so will 'my car flies off the track whenever the other guy's does' get replaced with the infamous 'every time I put three minis and an audi on my circuit the minis all flash their headlights and do 360's!" bug...

...only kidding
 

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Might sound dense but can you use non-digital cars on a digital track? not the lane change obviously but just normal use?

Also if you wanted to retain the normal power and controllers for using say Challenger (Just bought one 2nd hand but yet to use it
) could you not introduce some sort of switch between the wires to the track and the box. If the wires/PCB or whatever might damage digital surely if you switched the wires leading the the rail itself there'd be no way it could get damaged?

Might be complete tosh - not for the 1st time
 

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Analogue cars will not run on a digital set up

Challenger will not run on a digital set up

Yes - you can arrange a switch to the rails to choose between analogue and digital. Apparently scalext LC's do not link the 2 lanes electrically, if this is the case, then the powerbase must link them. So in theory you could have one lane digital and one analogue (but the guy on the digi lane must remember not to swap onto the analogue lane!
 

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So at worst could you just keep swapping out the digital power base from the normal power base to run normal cars. Would there be any issue with leaving the LC sections in place or must they be switched out also.

Astro - what I was thinking was that if I wanted to run normal cars I just switch off the digital powerbase and run normal cars. If I wanted to run digital I flick two switches which effectively break the wires in the normal powerbase between the rail and the base itself. Effectively the normal power base just becomes an ordinary track piece.

Scalex say that running a digital circuit but having a normal powerbase (albeit powered down) in the track will damage digital. However if digital was powered down would the normal powerbase and normal seperately powered rails damage digital? The latter seems more likely I assume so perhaps its digital which would need modifying.
 
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