View Full Version : 2x16 Serial LCD with Tpin = 16

Rick Brooks
06-09-2005, 05:18 AM
I've been playing with the 2x16 Serial LCD (non-backlit) with great results over the last few days.

I was wondering if I could use the Sout pin (physical pin 1) to control the LCD in place of one of the standard I/O pins.

I've use the Sout pin for communicating with RS232 devices (RoboteQ AX2550), but I've never tried using it for TTL serial communications.· I've also read the descriptions of SEROUT and only learned how little I know about serial communications.


06-09-2005, 05:33 AM
Negative.· Pin 16 - physical pin 1 - is only for communication with the PC via the serial cable.

Sid Weaver
Need a bezel for your LCD?

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Vern Graner
06-09-2005, 06:28 AM
Since I've also been experimenting with the serial LCD, I though I'd share a trick I discovered recently (though you may already be aware of this). Scott Edwards has this cool little bit of code to create a "rolling odometer" effect for the LCD. It sure "jazzes" up the display of numbers for counters and such:

http://www.seetron.com/an_odo1.htm (http://www.seetron.com/an_odo1.htm)



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Chris Savage
06-10-2005, 05:27 AM

·· One of our engineers and Tech Support guys hooked a Parallax Serial LCD Display up to a Stamp PLC using the programming port.· In order to do this, the Sout pin was tied through a 1K resistor to the base of a 2N3904 transistor.· It's emitter was tied to ground (Common with the display ground), and the collector was pulled high through a 10K resistor, as well as being connected to the LCD Serial pin.· So, yes, it can be done.

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

Post Edited (Chris Savage (Parallax)) : 6/9/2005 10:32:37 PM GMT

Rick Brooks
06-10-2005, 05:57 AM

Thanks for the response.· I·figured that it might take something to electrically invert the output, but hadn't actually wired up the circuit myself.· I had assumed that someone had already done that and could give a quick answer.

I'm sure that other users who are running short of I/O pins will use the circuit to gain one more TTL serial output.

As always, you guys are great.

·········· Rick

Chris Savage
06-10-2005, 09:24 AM

·· No problem...I can't take the credit for it though.· This actually started from something else.· But the guys here weren't about to let lack of I/O pins stop them from connecting that LCD!· I simply remembered seeing this post and thought I'd post their results.· I never thought to try this myself, but we do hope it benefits others.

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