Larry's Blog

Do you realize you can pick up older keyboards for one dollar! I have a few and use them to interface with my computer chips. I have done more work on my alphanumeric LCD (liquid crystal display). I can now set addresses and send ascii characters to these locations. The lcd controller automatically increments or decrements, each time you write to an address.

(more…)

Here is a version of a circuit that plays music. The program actually calls subroutines called doe,ray,me,far,sew,la,tea,doo. I have done lots of pgms on generating sounds, but this one attempts to get accurate mnotes of the musical scale. Some of the ideas came from an artice by G. Y. Xu in Nuts & Volts magazine.
So far this circuit plays Westminster Chimes and the theme played a race tracks for the start of the race. My circuit plays the notes as regular tones or as bell chimes.

(more…)

I have been posting info about my current project with emphasis on the SPEECH RECOGNITION aspects. Here is a posting I put out on YAHOO.
In my latest project utilizing several PIC microcontrollers, I need to have
communication between the system and the user – who may be a random
operator – say at an exhibit. Besides LCD’s and other types of displays, the
computer will communicate with a menu of voice messages using a
Chipcorder. But I want the operator to reply in a small vocabulary of spoken
words – IWR they call it – isolated word recognition.
Now I am beginning to learn there are a number of chips out there called
VPRs – voice recognition processors.
However, I want to try my hand at the nitty-gritty of speech recognition
circuitry myself. I am learning about A/Ds and DACs and I want to use a mike and an amp and digitize some individual words and see what the templates of the
sigs looks like. Then I would like to develop algorithms for comparing one
digitized template against another. Sound like fun to anyone?
Why let those engineers who developed these VRPs have all the fun? I like to
hear if anybody has tried one form or another of speech recognition.

I have developed several subroutines which have been tested and work pretty well.
dspyon – turns display on showing what is in memory
dspyof – turns display off
strtln – specifies line in mem for top of display
shftwd – my routine to shift a byte of data serially to DB0-DB7
write – after page, y-addres, and number of writes have been set
and content of byte to be written have been set, it
writes up to 64 byte-columns (1/2 of screen) across the screen
setpg – allows page to be set from 0 to 7
sety – allows Y address to be set from 0 to 64
reset – resets the LCD
enabx – performs an enable, enabling the action specified by the information on
the bus DB0-DB7 and setting of D/I pin and R/W pin.

(more…)

After much effort, I have made my HELLO WORLD pgm on a graphic LCD.
ALLELUJAH !!!

HERE IT IS!

I have set about programming a graphics type liquid crystal display. It’s specs are 128 X 64. The RAM memory on the device is like a bit map of the display.
The one’s and zeros in memory make up the picture displayed.
I haven’t gotten it to work yet , but the hardware and wiring have been completed.

(more…)

Well here it is! My setup for experimenting and building a project for the ISD2560 voice recorder chip.

You can see the cleaned up counter-top where I have assembled modules for the ISD2560 voice recorder chip itself, a PICmicrocontroller which talks to it, a
microphone card and an assembly for the loudspeaker output.

(more…)

Here they are ! 2 robots
the one on the right I call the SQUARE.
It goes in a straight line and turns to the right.
It repeats this, traveling in a square.
The robot on the left is called the LIGHT-SEEKER
It will rotate and search for a light source. When it finds it, it will beep and flash and head toward the light