EEVblog Electronics Community Forum
Electronics => Microcontrollers => Topic started by: legacy on November 24, 2013, 06:38:00 pm
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hi guys
googling for "signal generator" i have found this (http://www.aliexpress.com/item/DDS300-Signal-Generator-Output-Signal-DDS-PWM-100Hz-5V/1251401590.html) DDS300 board, it is a function generator module with two output signals , one is for PWM signal , the other is for the DDS signal. The module is TTL and has a 232 port, we can connect it to arduino (or to host computer) in order to choose a variety of waveform output , respectively {sine wave, square wave , triangle wave, heart} wave
The unit is cheap, you can also found it on ebay for ~$30/$40, unfortunately i can't find any documentation about the protocol, i recently got an .exe program which should handle the unit from an host computer running Windows XP.
anyone has already hacked it ? anyone has "sniffed" its serial protocol or knows something about ? let me know, it seems to be the coolest fish of the day in every hobbits electronic lab (probably the cheapest tool you can't miss) =P
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Are you kidding ???
At first glance i thought ATmega328 ,since 6pwm etc. fits , then i thought ... wohaa $37
100Khz hmmm ...
Get a real AD9850/51 it's even cheaper.
/Bingo
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anyone has "sniffed" its serial protocol ...
For $30+, I would hope that you don't have to sniff anything to use your "signal generator", if that thing can be called a "signal generator" at all.
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Get a real AD9850/51 it's even cheaper.
AD9850 generates only sine wave, DDS300 generates a variety of waveform output , respectively {sine wave, square wave , triangle wave, heart} wave
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For $30+, I would hope that you don't have to sniff anything to use your "signal generator", if that thing can be called a "signal generator" at all.
the program which handles this board is for Windows only and you don't need to sniff anything,you connect the serial cable between the PC and the DDS300 and you are ready to use the unit!
You need to sniff the protocol, or to get the protocol documentation, if you want to use linux, or if you want to connect the DDS300 to an embedded board, such as a linux-embedded board, or to Arduino.
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anyone has bought this unit or knows something about the protocol ? if not i will buy and reverse by myself.
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@bingo600
you mean something like this (http://www.electronics-lab.com/projects/test/013/) (AVR DDS signal generator) ?
(http://www.scienceprog.com/wp-content/uploads/2008i/DDS2/AVR_DDS_signal_generator_V2_0_block_diagram.jpg)
edit:
more reading about AVR DDS signal generator can be found here (http://www.scienceprog.com/avr-dds-signal-generator-v20/) (see notes)
AVR DDS signal generator has been inspired by this (http://www.myplace.nu/avr/minidds/index.htm) miniDDS project with Jesper’s DDS algorithm (enjoy it in avr asm)
DDS frequency range is from 0 to 65534Hz that is more than enough for testing audio circuits and other tasks.
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i hope sniffing is much faster than building a proper one from scratch. and i hope you have spare money to buy more proper one when you are done with this dds3000. and i hope you will enjoy the journey and i hope you good luck my "dear" ;)
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well :-//
sniffing may be faster than building a proper one from scratch if building something means designing the pcb, realizing the pcb, soldering components on pcb, testing the whole, fixing the jam, fighting with the fw, fixing it, finalizing the whole … etc
in short, sniffing a working object may be faster than obtaining a working object
btw, i am also learning a bit about DDS, especially if combined with CPLD or FPGA approach to provide "arbitrary wave" generator features.
very very interesting reading, so i have also bought a cheap book called "Digital Frequency Synthesis Demystified" by Goldberg
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While I know nothing about this module in question, or it's competitors, let's be realistic about how long it would take to discover the basic workings of the protocol.
You'll plug it into a PC (windoze or loonix), fire up any of the many free serial port sniffers out there, send it some commands from the given application software, and I'd bet within 20min you'll have a good understanding of how to control it.
It's taken me longer than that to decipher some Chinese datasheets in the past.
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exactly!
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Would this not be a better buy?
Sine, Square, Triangle Waves and 0 - 12.5MHz
http://www.aliexpress.com/item/AD9833-DDS-Signal-Generator-Sine-Square-Triangle-Wave-0-12-5MHz-Signal-Source-free-shipping/1295664251.html (http://www.aliexpress.com/item/AD9833-DDS-Signal-Generator-Sine-Square-Triangle-Wave-0-12-5MHz-Signal-Source-free-shipping/1295664251.html)
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Would this not be a better buy?
It doesn't offer an as convoluted solution, however.