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Grumble

Joined: Nov 23, 2015 Posts: 1310 Location: Netherlands
Audio files: 30
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Posted: Thu May 16, 2019 12:33 am Post subject:
Direct Digital Synthesis with the AD9102 Subject description: it has RAM on chip! |
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So I got some samples of the AD9102 DDS chip from Analog Devices.
The great thing about this chip is that is can put out a sine-wave, pos. saw, neg. saw, triangle wave, noise or a constant voltage, but the best feature is that this chip contains 4096 x 12bit RAM
So an arbitrary waveform generator is very possible with this!
The RAM can be used to store the waveform or may be used to modulate the frequency of the DDS.
The clock signal of both micro processors are put out to a post pin and used to clock the AD9102.
I made two experiment boards, one with an arduino nano and one with a small board I made with an ATxMega32E5. They both are capable to put out a sine wave to start with but I would like to use the internal RAM of the AD9102 but I'm afraid my programming skills are insufficient to whip up a decent C++ program. I think I will get it done but it would take a lot of efford for me and maybe there is somebody out there who is willing to help me out?
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_________________ my synth |
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MusicMan11712
Joined: Aug 08, 2009 Posts: 1082 Location: Out scouting . . .
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Posted: Fri May 17, 2019 4:58 am Post subject:
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Although I am not a DIYer, this project caught my eye.
Is this the on-board RAM you were talking about? "On-chip 4096 × 14-bit pattern memory" When I saw that, I thought it was a way to store 4096 14-bit single-cycle waveforms. If so and if those chips have good quality within the audio range of frequencies, that sounds like a cool thing to have.
I am looking forward to seeing and hearing your results.
Thanks for sharing.
Steve |
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Grumble

Joined: Nov 23, 2015 Posts: 1310 Location: Netherlands
Audio files: 30
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Posted: Fri May 17, 2019 8:24 am Post subject:
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There is an error in the datasheet, the DAC is 14bits wide but the RAM is 12bits.
The frequency range when clocked with 16MHz is 0.95Hz up to in the MHz region.
It should be posible to upload a signal up to 4096 values. _________________ my synth |
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MusicMan11712
Joined: Aug 08, 2009 Posts: 1082 Location: Out scouting . . .
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Posted: Fri May 17, 2019 10:09 am Post subject:
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Grumble wrote: | There is an error in the datasheet, the DAC is 14bits wide but the RAM is 12bits. | Thanks for the clarification/additional details. Looking forward to seeing what you do with the chips.
Steve |
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