E-CodeDiscrete PID step response — a TI-84 Plus CE program
PIDSTEP is a TI-BASIC program for the TI-84 Plus CE. A first-order plant G/(τs+1) sampled with a zero-order hold, under a positional discrete PID: table of the output at every sample, then the final value, peak, percent overshoot, steady-state error and last control signal.
What it asks for and what it shows
It asks for 8 values at its prompts. In the example below it shows Y LAST, Y MAX, %OS, SS ERR, U LAST.
Example run
One of its oracle test cases: “P only leaves an offset”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | 2 |
| Input 2 | 5 |
| Input 3 | 0.5 |
| Input 4 | 1.5 |
| Input 5 | 0 |
| Input 6 | 0 |
| Input 7 | 1 |
| Input 8 | 60 |
| The screen shows | |
Y LAST= | 0.75 |
Y MAX= | 0.75 |
%OS= | 0 |
SS ERR= | 0.25 |
U LAST= | 0.375 |
How it's checked
5 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 31 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Discrete PID step response” (PIDSTEP).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Second-order step response metrics
- Polynomial roots and stability
- Bode point and stability margins
- RC, RL and RLC transient response
- RC circuit charging transient
All TI-84 Plus CE engineering programs · All TI-84 Plus CE programs