Reasonably experienced and 'a week' can mean vastly different things... It's certainly easier to keep the cost down with longer time-frames.
For a focus on electronics rather than implementing some kind of toy 'algorithm accelerator', I find low-hanging/interesting projects where the combination of requirements exceed a micro's peripheral capabilities - i.e. multiple input/output/processing tasks which could be performed on a micro individually, but adding synchronisation or latency requirements makes it rather non-trivial.
- Very wide/parallel input/output tasks: ADC/DACs for higher samplerate/bitdepth/channel count than typically accessible with even high-end micros
- Implementing unique/specialised protocols which would have required bit-banging, abuse of timer/other peripherals on a micro (i.e. interesting things people achieve with PIO blocks on RP2040 etc)
- Signal processing: digital filters and control systems are great because you can see/hear/interact with the output which can help build a sense of achievement.
When starting out, it's also less overwhelming to start with smaller parts and allocate the budget to the rest of the electronics. They're still incredibly capable and won't seem as under-utilised. Some random project ideas:
- Find a sensing application that's interesting and then take it to the logical extreme - arrays of photo/hall-effect sensors sampled at high speed and displayed, accelerometers/IMU sensor fusion
- Laser galvanometers and piezo actuators are getting more accessible
- Small but precise/fast motion stages for positioning or sensing might present a good combination of input, output, filtering and control systems.
- With more time/experience you could branch into more interesting (IMO) areas like RF or imaging systems.
With more info about your interest areas I can give more specific suggestions.
Good list, thanks. I have a couple of years professional experience as a software dev and worked in the embedded space too. Nowadays I am in security and that is definitely an area of interest.
I only dabble with recreationally reverse engineering industrial/consumer grade HW and following blogs/conferences, so I can only provide a rough shotgun of search terms to try and hit something you're interested in:
- The Glasgow interface explorer is an example of a smaller FPGA making interface level RE tooling more accessible.
- The Chipwhisperer hardware has a focus on power supply glitching, side-channel attacks and general hardware security education/testing.
- There's a handful of FPGA-based implementations intended for high-speed protocol sniffing/MiTM (TCP/IP, USB and CANBus are both pretty common) on github etc, Cynthion is one example.
- Some recent projects have been trying to implement and improve the FOSS ARM Cortex programming and trace experience, Orbuculum ORBTrace probe is an example though the benefits aren't fully realised yet.
- In an odd use-case for an FPGA, I've personally seen hardware that enforces brutal/paranoid DRM/licencing via customised downloaded bitstreams to guards against reverse-engineering/copy efforts, all to most likely run a soft-CPU. I've read (unsubstantiated) that this approach appears on some military hardware.
- Slightly adjacent to specific FPGA projects, but the SDR tooing ecosystem has lots of cool stuff to play with for wireless signal identification/spoofing/re-implementation. HackRF, LimeSDR, GNUradio etc. If you want to get deep then there's lots of overlap with custom FPGA implementations.
For a focus on electronics rather than implementing some kind of toy 'algorithm accelerator', I find low-hanging/interesting projects where the combination of requirements exceed a micro's peripheral capabilities - i.e. multiple input/output/processing tasks which could be performed on a micro individually, but adding synchronisation or latency requirements makes it rather non-trivial.
- Very wide/parallel input/output tasks: ADC/DACs for higher samplerate/bitdepth/channel count than typically accessible with even high-end micros
- Implementing unique/specialised protocols which would have required bit-banging, abuse of timer/other peripherals on a micro (i.e. interesting things people achieve with PIO blocks on RP2040 etc)
- Signal processing: digital filters and control systems are great because you can see/hear/interact with the output which can help build a sense of achievement.
When starting out, it's also less overwhelming to start with smaller parts and allocate the budget to the rest of the electronics. They're still incredibly capable and won't seem as under-utilised. Some random project ideas:
- Driving large frame-buffers to display(s) or large sets of LED matrices at high frame rate - https://gregdavill.com/posts/d20/
- Realtime audio filters - the Eurorack community might have some inspiration.
- Multi-channel synchonous detection, lock-in amplifiers, distributed timing reference/control,
- Find a sensing application that's interesting and then take it to the logical extreme - arrays of photo/hall-effect sensors sampled at high speed and displayed, accelerometers/IMU sensor fusion
- Laser galvanometers and piezo actuators are getting more accessible
- Small but precise/fast motion stages for positioning or sensing might present a good combination of input, output, filtering and control systems.
- With more time/experience you could branch into more interesting (IMO) areas like RF or imaging systems.
With more info about your interest areas I can give more specific suggestions.