ECE 441 · Week 5
Modern Computer: Secure Infrastructure
A method names instruments, steps, and what to record.
Week 5 of 10 · Solitude
ECE 441 · Week 5 · In class
A method names instruments, steps, and what to record.
- It does not report the numbers.
- The three measurements are boot time, idle power, and one peripheral transaction.
- For idle power, the instrument is the USB power meter on the bench, placed between the supply and the board.
- The unit is the unit that meter prints.
ECE 441 · Week 5 · In class
A method names instruments, steps, and what to record. (continued)
- Copy the instrument and the unit.
- Those two are the homework.
ECE 441 · Week 5 · In class
Have your partner read one step aloud.
- If they cannot follow it, fix the step.
- The sheet still has no measured numbers on it.
ECE 441 · Week 5 · Lecture
A method, not a result
- A method names the instruments, the steps, and what to record. It reports no numbers.
- Its reader is a classmate who was not there, with the same bench and nothing else.
- If they follow it and get a different number, the method is what gets examined.
ECE 441 · Week 5 · Lecture
The three measurements
| Quantity | The method must say |
|---|---|
| Boot time | The start event, the end event, the clock |
| Idle power | Where the meter goes, what idle means, how long to read |
| One peripheral transaction | Which device, which command, what success looks like |
ECE 441 · Week 5 · Lecture
What a good step looks like
Step 4. With the board at the login prompt for
60 s and nothing typed, read the meter
display once every 5 s for 1 minute.
Record: the twelve readings, the unit shown,
and the meter's model name.- One action, its condition, and what to write down.
- Every wait has a length, every reading a unit, every tool a name.
ECE 441 · Week 5 · Lecture
Common gaps in a method sheet
- "Boot the board": from cold or warm, and from which card?
- "Measure power": where in the circuit, and averaged how?
- "Read the sensor": which bus, which device, which command, what output?
- A step that only works because you remember something the sheet does not say.
ECE 441 · Week 5 · Lab
Lab
- Write the method, not the numbers: instruments, steps, and what to record for boot time, idle power, and one peripheral transaction.
- Second pass: have your partner read one step aloud and fix a step they cannot follow.
- Assemble the lab hand-in: A method sheet: instruments, steps, and what to record for boot time, idle power, and one peripheral transaction.
ECE 441 · Week 5 · Lab
Hand in
A method sheet: instruments, steps, and what to record for boot time, idle power, and one peripheral transaction.
ECE 441 · Week 5 · Homework
Homework
- Write the instrument the lecture names for idle power, and the unit it reports.
ECE 441 · Week 5 · Homework
Turn in
The instrument and the unit.
ECE 441 · Week 5 · Read
Read
On the lab site: Module 2, First power-on and voltage rails, shows the meter. No basic module grades a method sheet another student can run. This week is past Module 12.
ECE 441 · Week 5 · Next
Week 6
A peer rerun changes nothing in the method.