The ScanConverter is simply a "plug" that plugs into the ALDL port of the Fiero and converts the coded datastream in realtime to an RS232 ASCII datastream that any computer with a serial port can read. This includes Palm Pilots, Windows CE computers, Newtons, etc. It is the size of a matchbox and uses an 8051 based microcontroller with on-board Flash-EEPROM as the workhorse. The ScanConverter works with all V6 Fieros and the 84-86 L4's, but not the 87/88 DIS 4 cylinder cars.

There is virtually no limit to the number of ways you can display the information you can read with the ScanConverter. The image to the left was generated from an approx. 90 second run, visualized using MS Excel and only three items. There are over 20 more to choose from, in any combination. Combine this with the power of Excel and you begin to get an idea of what you can do with this tool. Click here to download the Excel file to play with the data yourself!

Hardware

I had the idea to build an intelligent plug a few years ago on a flight to London. I scribbled the schematics on a napkin (really!) and got to work when I got home. The original concept was to keep the parts count at a minimum and hence keep the circuitry cheap. Someone on the Fiero mailing list pointed out that my cheapo transistor/pullup inverter might be incompatible with some desktop computers. True. So I decided to use a Maxim chip for true RS232 levels. A little more expensive, but a lot more compatible.

The switch is used to change between Trouble Code mode (in which only trouble code numbers are output) and "normal" mode. The LED is on whenever the ScanConverter has received a complete frame and is transmitting it to the PC.



The circuit board design can be found here.

Software

Of course, if you want to look at the data the ScanConverter provides, you do need some software as well. Using Excel, formatting the ScanConverter's output is only a few mouse clicks away:
1. Capture data with Terminal program
2. Save file as ASCII
3. Open ASCII file with Excel
4. Click on data columns to chart
5. Press Chart button

Of course, you can also use real-time display programs, or write your own. Here are several programs for different platforms that demonstrate what the ScanConverter can be used for. Note: These programs don't do anything useful without the ScanConverter.

DOS/Qbasic/V6	If you would like to see what the QBasic program that formats the ScanConverter's output looks like. Works in a DOS box under Windows too!
DOS/Qbasic/L4	This is the 4 cylinder version of the Qbasic program.
Windows/Freeware/V6	Freeware program written by Peter Wieners. Partially German, but looks still very nice! Download the latest version directly from his website by clicking here. Please direct comments or suggestions directly to the author.

If you have written a freeware/shareware program to go with ScanConverter, you can email it to me and I will put it here for others to download (space permitting). If you want to supply a link instead, that's fine too. As far as I know, programs have been written for MS Windows (of course), the Newton, and I am planning on writing a PalmPilot version. It would be cool to use the infrared feature of the Palm III for this, then one could have a hidden switch in the car to turn the ScanConverter on, and you could wirelessly diagnose your car. I just love that idea...

The software inside the CPU is in revision 1.2 and runs very stable. Oh, if you're looking for the source code or a hex dump of it, look no further. I am not providing the source code or binaries, because I don't want people making money off of it. A lot of effort went into this gadget, and I don't want to see my work published on all sorts of sites. Instead I can provide a CPU at cost if you want, and I can also provide a completed unit (built and tested), if you're not handy with electronics. The prices are:
 
 

ScanConverter pricing

Item	Price (US$, postal money order)	Shipping (airmail to US)
ScanConverter programmed CPU	$25	$5
ScanConverter unit (built and tested)	$60	$15

Email me for details.

Another note: I can not help you debug the circuitry if you decide to build a ScanConverter yourself. Sending a board back and forth across the pond is not exactly cost effective, and I'd be stuck with the postage bills.

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Here is the parts list:

Qty	Description	Conrad Part Number
1	AT89C2051 with program "ScanConverter"	N/A
1	MAX232ACSE	N/A
1	78L05	18 30 24
1	3mm low current LED, red	14 59 98
1	LL4148	14 09 02
1	ZPD4V7 SMD	14 17 80
1	12 MHz crystal	16 87 26
1	1.5k Ohm SMD	40 25 67
1	1k Ohm SMD	40 25 40
1	10k Ohm SMD	40 26 64
2	33p SMD	46 00 95
3	100nF 1206	45 24 40
5	100nF 0805	45 25 05
1	2,2uF/16V SMD	48 14 67
1	Switch SPST	70 80 54
1	20 pin socket	18 98 39
1	9 pin Sub-D fem	74 20 82
1	Sub-D case	71 12 84
1	9V battery clip	61 56 50

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