************ BIKE.Z80 **************
First, I'd like to get some feedback if anyone is interested in this program.
So please drop me an e-Mail (bernhard.weirich@aon.at).
I'm grateful for every comment even if it's simply: You are crazy!

Why I wrote this program:
I always wanted to have a bicycle computer that supports special functions that no bikestore
offered. So I had to create my own bicycle computer. Because I own a TI-83 Plus the
program was written only for this calculator and won't work with any other.

After having invested some months' work for software
and hardware, the TI-83 Plus program BIKE supports the following functions,
which are updated every turn of the wheel:
- Speed (this was tricky since time measurement in ASM is not easy to implement)
- Maximum speed (I hope that nobody ever exceeds 99km/h or 99mph, otherwise he will find a 
 messed up max speed)
- Counter for km per day (this was the first and easiest function)
- Counter for km total
- Precise average speed (2 decimals)
- Elapsed time 
Special things:
- Countdown
- ETA (Estimated time of arrival), based on average speed! (display startes after 1/8 of distance)
- Diagram: distance / time etc. after quitting the program
- All information is simoultanously displayed (except the diagram)!

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How to use it:
- You need the software - prgmBIKE (, prgmSTART, prgmCALC) grouped in BIKE.8XG

!Don't rename prgmBIKE - it uses a program write-back technique to store the total counter!
To run the program you must store the circumference (in cm) of the wheel into var C.
If you want to use the unit mph, divide the circumference by 1.609 - and round to an 
integer value.
To specify the countdown value store the amount of kms (or miles) into var D - 
you may specify 5 decimals. 
Having set those vars Asm(prgmBIKE) will start the program.
I 've added a BASIC program (prgmSTART) that stores the circumference at its first start,
asks for the distance to go and starts the assembler program.
To exit press "Clear".
Another BASIC program (prgmCALC) will convert the numbers from LCYCLE to a diagram.
That's the software.

- Then you must produce the hardware yourself!

Hardware:
This is again not easy.
There must be something that tells the calculator, that the wheel has turned once.
With the TI it works like every other bicylce computer. 

What you have to do:
1) There must be a magnet fixed on the wheel. (perhaps from an "old" computer)
2) You must be a bit inventive!
 You need the appropriate socket (2.8mm stereo - I think) and the TI cable (for connecting 
 two units). You must fix (probably solder) an electronic device (Reed sensor 
 - conducts voltage only when exposed to magnetic fields) to the socket.
 The socket should offer three possibilities to connect the Reed sensor with. Two which
 are looking similar and one that is different. Connect the somewhat different and any 
 of the others (or both parallel) with the Reed sensor.
 
 To test it connect the cable with the TI-83 and the socket. 
 The cursor should blink as usual. (If not you may have failed to solder correctly?)
 Hold a magnet close to the REED-sensor. The cursor on the screen should stop blinking.
 If not: you either conected the wrong ends or made any other mistake.

 If this works you must try whether the magnet on the wheel produces the same effect.
 When everything had worked you should find a cover or something to protect it (or not).
 And perhaps you find a good way to fix your TI to the bike - good luck with this!
 If the hardware is ready - the software was my problem - you should try it and tell me
 about your experiences!
 
 If there are any problems you can ask me 
 =======> bernhard.weirich@aon.at
 
 There's just one key that the program responds to: Clear - exit. 
****************************