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ShakerRapid
08-25-2006, 03:28 AM
We have hooked-up the reader ant powered it up.

Good news is that the LED does he Green/Red thing as expected.

Bad news is we can't seem to see the output stream.

Our hope had been to use HyperTerminal on a PC to see the message.
2400 bps 8 - 1 etc but no visible results.

Hanging a scope on the Sout lead shows something happens on the Sout pin when we hit the button grounding the enable pin.

Does the reader take a while to think about the stream?
Maybe we are being too impatient?

Anybody got some clues for a newbie?

Regards,

Chris Savage
08-25-2006, 04:43 AM
How are you connecting the RFID Reader to the PC? If directly that won't work. The RFID Reader output is TTL level non-inverted. PC uses RS-232 level inverted.

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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

John R.
08-25-2006, 04:43 AM
You mention HyperTerminal, are you hooking the reader up directly to a serial port on the PC?

This will probably not work, as the reader works on a TTL signal, not at full fledged RS232 voltages.

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John R.

8 + 8 = 10

ShakerRapid
08-25-2006, 04:51 AM
Thanks,

OK, it sounds like we need to buy a STAMP and have "it" talk to the PC.

Is that a sensible plan?

Or, is there an easy level changer circuit available?

steve_b
08-25-2006, 05:20 AM
I believe a MAX232 chip would work.

Google MAX232

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Steve

"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

John R.
08-25-2006, 07:32 PM
If all you want to do is "see" the output, you could also buy a serial LCD display from Parallax, and the RFID reader will "direct connect" to that.

If you want to go the "STAMP" rout (a very viable alternative), you may also want to look at an SX chip. With the SX deals going on now, you can get into it very inexpensivly and program with SX/B.

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John R.

8 + 8 = 10