Thank you, Mr. Hylands.

I only need to connect one of the pins - either the CMOS with the onboard STTXD resistor removed, or I can use TTL Data (inverted) with an inverter/TTL Data (inverted) in RxD on the MiniDin.

Ok, wish me luck! :p

 - Michael

On Tue, Aug 5, 2008 at 1:31 PM, Dave Hylands <> wrote:
Hi Michael,

On Tue, Aug 5, 2008 at 10:14 AM, Cryptographrix
<> wrote:
> I recently purchased the consoleLCD16-vx along with a verdex and
> netwifimicrosd stick, and have been looking to integrate it with SparkFun's
> ID-20 RFID reader.
> First question - While looking at the pinouts on the consoleLCD16-vx, I
> noticed that the board has breakouts for 'AC97' what are the pinouts for
> it and can I use it for audio?

The best place to determine the pinouts is by examing the schematics.

You'll need to install Eagle (free):

I haven't used version 5 of Eagle, but have used verion 4.

> Second question I understand that I need to remove the resistor labeled
> STTXD to use the STUART breakouts, but I'm trying to figure out which pins I
> should use from the ID-20 RFID reader in to pin 4 (RxD, I understand?), as
> the RFID reader has CMOS on pin 8, and TTL Data (inverted) on pin 9.
> The rfid reader has no inputs, from what I understand it behaves very
> similarly to a magnetic card reader, except that I will be setting it to use
> ASCII mode, hence CMOS/TTL Data (inverted).
> What is CMOS/TTL Data (inverted)?  Which should I use in to pin 4/RxD?  Do I
> need to use a resistor or an inverter as noted on
> ?

If the CMOS output were at 3.3v, then it could be connected directly
to the RxD pin. Since the ID-20 runs at 5v, you'll need to do
something about the voltage. Using an inline 10k resistor should be

Now if you leave consoleLCD board as a RS-232 level (i.e. don't remove
the resistor), then you can hook up the TTL Data (inverted) directly
into the RxD line on the MiniDin connector. While not true RS-232 most
RS-232 device will recognize it. Otherwise, to connect this particular
line to the console LCD when configure as a logic-level input (i.e.
on-board resistor removed), then you'd need to put an inverter inline.

Dave Hylands
Vancouver, BC, Canada

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