12-13-2018 11:09 AM
01-08-2019 06:28 AM
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!
01-08-2019 06:56 AM
@crossrulz wrote:
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....
01-08-2019 07:17 AM
@crossrulz wrote:
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?
01-08-2019 07:58 AM
wiebe@CARYA wrote:
@crossrulz wrote:
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
01-10-2019 12:38 PM
@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. 😄
01-11-2019 02:16 AM
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.
01-11-2019 10:45 AM
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:
01-14-2019 07:43 AM
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
02-26-2019 10:09 AM
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).