I'm familiar with basic PID controllers and have used them before. But the diagram given doesn't really make sense to me:
Code: Select all
*
* The PID Controller algorithm itself is implemented in FPGA.
* There are 4 independent PID controllers, connecting each input (IN1, IN2)
* to each output (OUT1, OUT2):
*
* /-------\ /-----------\
* IN1 -----+--> | PID11 | ------| SUM & SAT | ---> OUT1
* | \-------/ \-----------/
* | ^
* | /-------\ |
* ---> | PID21 | ---------- |
* \-------/ | |
* | |
* | |
* | |
* /-------\ | |
* ---> | PID12 | --------------
* | \-------/ |
* | ˇ
* | /-------\ /-----------\
* IN2 -----+--> | PID22 | ------| SUM & SAT | ---> OUT2
* \-------/ \-----------/
*
*/
What does "SUM & SAT" mean? What is this step doing, actually implementing the PID algorithm?
Why are there 4 PID controllers? There are only 2 high speed inputs! It seems to me like you'd need 1 controller per input. So this makes no sense to me.
Why do the 2 high-speed inputs seem coupled? I just want to use one high-speed input to produce a signal on one high-speed output. Maybe I'll have two experiments going at once, necessitating the use of both inputs and outputs, but in either case I cant imagine wanting the inputs to be coupled.
Lastly, somewhat unrelated, but my redpitaya cannot be connected to the internet... where can I find the apps described on this page? http://bazaar.redpitaya.com/ There are no links anywhere on that page! Why does it even exist??
Thanks for helping to resolve my confusion!