1- Write an i2c driver, to access the eeprom we have in the tdc board.
It can use the hardware support in the microcontroller, or just rely
on gpio pins.

2- Identify where is the race condition in commit 02fa9a5f. This
is the alternative __sched implementation that I then reverted from the
repository.

3- Use the leds in the mini-preempt application in order to actually
"see" preemption: one led for the fast task, one led for the slow
task, and one for the main function, that must turn off when
preemption happens.

4- Describe how you can use the "timestamp_fraction" argument to the
interrupt handlers to get interrupt timestamps. Please remember that
a timestamp has two components: the jiffies value and the fractional
counter.

5- If the system is using preemption with a number of tasks, use of
the stack is fuzzy, because the various tasks will overlap in
unpredictable ways. You are not sure about stack use in production,
despite your tests during development.  Please find a way to measure
the worst case use of the stack, to validate you project before
deployment.

6- Back to malloc. Sometimes tasks may need temporary storage, but it
is released before the iteration of the state machine (i.e. before the
job returns).  If more than one task needs temporary storage at
each iteration, it may make sense to allow sharing, through malloc/free
(but if we have preemption the stack problem above surfaces again.
Please draft or write a malloc implementation suitable
for this use case. Also, find a way to ensure no out-of-memory will
ever happen.

7- Let's imagine you are asked to make a relay board, or an array of
smaller boards. Your client wants to drive 50 low-power lamps, but you
fear the number will increase later: all clients are the same in this
respect. It's just on-off, no PWM is needed.

Operation is mostly unattended, and it's paramount that it works for a
whole week.  If some component fails, it should be quickly replaceable
by non-technicians, and you are especially concerned about the
solid-state relays -- no audible ticking is allowed at the deployment
site.  Please lay out the ideas for your implementation.