Jump to content

Recommended Posts

I needed to be able to watch signals from hundreds of Hz  to 10Khz . While reading the msp430 family manual found the Data Transfer Controller (DTC) that can be put to work with the ADC . 


So the original launchscope by NJC streams data one sample at a time , and that is why it is so slow . So using the DTC we can actually get near the 200Ksps . 


So I use an array of 200 integers (400 Bytes . I didn't want to leave the launchpad without ram, just 512B for the msp430g2553




Link to post
Share on other sites
  • 1 month later...

Hey @@simpleavr, the datasheet of the msp430g2553 says the ADC is capable of "up to 200ksps", that means, a 10Khz signal will have only 20 samples of resolution (at max sampling speed) for a complete wave (so it is not gonna look smooth at all) . So a 200KHz signal should seem like a square wave . But that wouldn't be helpful nor reliable for signal viewing.  


I don't know why the limit is at 200ksps and I don't know what would happen if you try to sample at , say, 1Msps, using the 16Mhz config. Since I am using the burst mode (with the DTC) I don't know either if the msp430g2553 will let you use more than this limit (as I said I only achieved 180ksps, and I didn't see if it was the clock's fault) . But it can use any clock source within the micro . so theoretically it is possible :) . Let me know if you achieve higher samples per second 


The stellaris, though, seems like a much better option for this.

Link to post
Share on other sites

thanks for your reply.


actually the slau144 says "greater than" 200ksps. so that's why i wonder "how much greater".


at about 200ksps u would fill up 200 samples in 1/1000 sec.


uart at 9600bps u xfer 200 x 5 bytes (4 hex char + line feed) = 1kbytes = 8k bits or about 1 second to xfer result. i.e. 1 sec refresh.


did u try to make in continuous and does it look good (or useful to u)?

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...