[McHUG] Don't trust the comments!

[Peter Morton]

Rich-

I wrote a library of LCD functions that use the most-significant data nibble 
for the Arduino.  The library is very similar to the one I prepared for the 
ET ATMega128 development board and the Futurlec 16x2 display, and is a 
modified version of the LCD library I found in the CodeVision AVR library.

It does not use the R/W pin on the lcd.  It uses delay statements to allow 
enough time between writes to ensure the LCD is ready for the next write. 
So, it is not very efficient but works well in my applications.  I ground 
the R/W, data 0-3, and Vp (contrast) pins.

Let me know if you're interested.

I finally finished construction of my dual synthesizer-in-a-box, and am in 
debug and writing-software mode.  Last night I discovered the DDS60 does not 
always start up at power-up.  It's the first time I've powered up both the 
BBB and the DDS60 at once.  So, I have to go back and look at the power-up 
initialization of the AD9851 when the chip is switched from parallel to 
serial data entry.  The DDS60 data sheet has a lot of discussion on this 
topic.  I may have to hold the inputs data, clock, and  load inputs low 
until after power-up and then use the BBB to perform the initialization.

Both programs I wrote previously for the DDS60 and the Si570 work in the new 
box.  I just have to combine the two programs.  I'm also thinking about 
adding morse to the program.

Right now I'm using all but one of the BBB pins.  4 are used for frequency 
selection switches, 6 for the lcd, 3 for the DDS60, 3 for the Si570 (added 
the output enable line), 1 for the synthesizer select switch, and 2 reserved 
for the serial programmer.  That's 19 of 20.

Earlier this year I ordered a 16x2 back-lit LCD from Futurlec and one from 
Digikey (Lumex).  The Lumex requires about 100 mA for the back light LEDs, 
but the Futurlec only requires 14 mA, and has a series 150 ohm resistor on 
the LCD board to limit the LED backlight current, so the backlight is all 
set up to run on 5V.  So, I applied 5V to pin 15 of the LCD board and ground 
to pin 16.  I'm using the Futurlec display in the dual-synthesizer-in-a box. 
The display is powered by the BBB +5V.

-Pete


----- Original Message ----- 
From: "Rich Mitchell" <geobra at att.net>
To: "McHUG Reflector" <mchug at mailman.qth.net>
Sent: Wednesday, December 03, 2008 9:50 AM
Subject: [McHUG] Don't trust the comments!


McHUGgers,

[snip]