Mag Card Reader

[Melanie]

Dear Mrs. Melanie - Ohhhh... don't marry me off yet... I'm still a Miss Melanie! Thank you for the compliments.

I don't recall giving advice about putting a Capacitor anywhere... perhaps it was Bruce. The Card-Detect is usually accomplished by either a photocell or a microswitch. Some cheap readers have the sensor positioned in front of the Read-Head so a card is detected as soon as it is inserted into the slot, but as it is swiped it is still travelling past the Read-Head as it clears the sensor therefore giving too early a warning that the card has been removed, so spoiling the read. A Capacitor could then be inserted to delay the card-detect signal... perhaps that was the reason, otherwise I just can't remember what it was for.

Anyhow, if you're only at the start of your project, I wouldn't worry about it until you meet any problem.

If you are going to read more than one track at the same time, then you will need either more PICs - one for each track, or a different PIC, as I recall (remember this was THREE YEARS AGO in 2002) the 16F84 pretty much maxed out on that RAM Buffer, and the 16F628 was only a bit better. You should be able to do it in one PIC, but will need to chose one with a lot more RAM and depending on how many tracks, you might need a speed increase beyond 4MHz.

Best wishes on your project in trying to make the world's smallest reader - Have fun.

[DynamoBen]

I too am using the MagCard code. I'm almost to the end of my project. I'm using a standard card reader (not serial), I2C memory to store account numbers, and RS-485 interface.

The only difference in my project is I'm stripping out only the account data and storing it. For security reasons I'm not collecting the balance of the information. (expiration date, pin hash)

I'm with Melanie in that you should start writing some code and experiment a little. I have modified her code very little and her code worked right away.