BreakPoint

cancel
Showing results for 
Search instead for 
Did you mean: 

Carnac the Magnificient - sarcastic answers to serious questions/comments

giphy.gif

Matt J | National Instruments | CLA
Message 221 of 298
(5,415 Views)

Trouble with DIO !

Did you know that a digital line cannot output a sine wave?  I am in just complete shock that a switch cannot just output whatever value I want!


GCentral
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines
"Not that we are sufficient in ourselves to claim anything as coming from us, but our sufficiency is from God" - 2 Corinthians 3:5
Message 222 of 298
(5,320 Views)

@crossrulz wrote:

Trouble with DIO !

Did you know that a digital line cannot output a sine wave?  I am in just complete shock that a switch cannot just output whatever value I want!


Of course with 8 DOs (and a few resistors) you can make 1 8-bit AO...

 

I can hear his manager say: I still thing we need to find a software solution....

Message 223 of 298
(5,313 Views)

@crossrulz wrote:

Trouble with DIO !

Did you know that a digital line cannot output a sine wave?  I am in just complete shock that a switch cannot just output whatever value I want!


BTW. this reminds me of my old 8088 PC. It had a speaker that only beeped at one frequency. Some clever people came up with the idea to PWM the beep, resulting in speech output from the speaker.

 

This is actually getting way to close to a serious answer... Maybe I should post it in the original thread?

Message 224 of 298
(5,311 Views)

wiebe@CARYA wrote:

@crossrulz wrote:

Trouble with DIO !

Did you know that a digital line cannot output a sine wave?  I am in just complete shock that a switch cannot just output whatever value I want!


BTW. this reminds me of my old 8088 PC. It had a speaker that only beeped at one frequency. Some clever people came up with the idea to PWM the beep, resulting in speech output from the speaker.

 

This is actually getting way to close to a serious answer... Maybe I should post it in the original thread?


Yes dangerously close to being a useful idea.

 

Pulse Density Modulation  (used by digital microphones in cell phones) only needs a low-pass filter.

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
Message 225 of 298
(5,305 Views)

@Ben wrote:

Pulse Density Modulation  (used by digital microphones in cell phones) only needs a low-pass filter.

 


And we even have code I wrote over 10 years ago. 😄

 

Message 226 of 298
(5,322 Views)

Deta Sigma Simulation? Is that Delta Sigma Simulation? Is that the same as Pulse Density Modulation?

 

I'll probably need to read some wiki's on that. I never can remember the term Pulse Density Modulation when I need it.

0 Kudos
Message 227 of 298
(5,280 Views)

wiebe@CARYA wrote:

Deta Sigma Simulation? Is that Delta Sigma Simulation? Is that the same as Pulse Density Modulation?

 


It is one way to create a PDM bit stream, but I am sure there are others. Straight from Ben's link above:

 

PDMDS.png

Message 228 of 298
(5,261 Views)

PDM...

 

As an "old scope jockey" I see the decoding as exactly what I would expect if I had a bit stream driving an RC circuit where the RC timeconstant acted as low pass filter. IT could also be handled with moving average where the window size was large enough.

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
0 Kudos
Message 229 of 298
(5,203 Views)

Here's a 'perfect' reply for someone asking what the perfect solution would be:

As seen (not sarcastically though) in the wild in this thread: By Yamaeda, in this thread (so kudo that one if you like).

Message 230 of 298
(5,043 Views)