Arbitrary Waveform Generator Design with microcontroller

[landbattery]

I am new to this website

http://www.eng-tips.com.

I have been tasked to design an arbitrary waveform generator. I have constructed a block diagram. I want to send data via the PC to an interface driver, such as the MAX232 RS232 interface driver, over the RX/TX lines to the microcontroller. I want the microcontroller to process the values to my D/A converter, and then amplified by my op-amp, LM741.The frustrating problem I am having is the microcontroller portion. Where to start how to create an external trigger circuit for this arbitrary waveform generator. One of the requirements I need to fulfill is to have the generator generate a signal ay a 2sec rate. If any one has idea informative websites on introduction to microcontroller design, it'll be greatly appreciated. Have a safe 4th of July.

 

[STUONTIPS]

To complicated for a simple answer, however have you considered the use of LPT1 as the control source for your D-A the code could then be written using a high level langauge?

 

[piedade]

so the microcontroler is only used to recieve the serial data from the pc and aply it in the correct maner to the D/A chip ? is that what you want ...
The microcontroler acting as an interface and generating the control signals required by the DA ?
try to be more specific

 

[rickcappels]

If you only need to update the DAC value once per second, you can use an Atmel AT90S2313 with object code I've posted on the web.


These are basic interpreters that reside in single chip computers and use on-chip RAM and have connections for an RS-232 port. You can download the hex files and program the chips, or have someone program the chips for you, then you can write the program to update the ports yourself in a very simple BASIC. Complete documentation as well as the hex files are on the web site.

Take a look at

http://www.projects.cappels.org

and scroll down and click on the "Mostly Firmeare" secion and click on "AttoBasic Byte-Wide interpreter for AT90S2313",

This is a very small BASIC interpret that runs on a US$2.50 RISC microcontroller. It can output byte-wide data to the 8 bit I/O port as you send it from your host via RS-232.

Another choice would be to click on "AttoBasic Byte-Wide interpreter for AT90S8515/ATMEGA8515 and ATmega163". These versions of the interpreter run on chips that have more internal RAM available, so you can run a small program inside them that updates the output port autonomously from an array in RAM, whcih would be downloaded from your host, and port updates could be done by cue from your host, as well. Or any other way you want to approach it. It might only take an hour or two to get your simple application running once you get the BASIC interpreter into the chips.

Oh...and did I mention that you can store your program in the on-chip EEPROM and have it automatically start running at power-on reset?

Just an ideal.

Let me know if you need any help with this.

Dick

 

[landbattery]

This is what I am attempting to do with this generator:
-Transmit data from a file (such as matlab) to the microcontroller.
-The microcontroller will be programmed to obtain the data and send it to the D/A at a specific transmit rate.
-The transmit rate will be performed via software code or by an external trigger. By an external trigger? I am thinking I can take a signal from a function generator and use that source as an external trigger for the microcontroller circuit. Set it at 2 Hz ping rate.

Piedade - that is correct.

Stuontips - never thought of that idea.

Rickcappels - I will look into that idea.

Glen