For no good reason other than avoid the >30C heat, I browsed some of the old usenet postings I’ve saved over the years. I’ve reproduced one below to illustrate how things have changed, maybe for the better, maybe not. I have a couple of such books, and can confirm that they do have chapters on building and using your own X-Ray machine, including such gems as noting that if your skin reddens you are probably using it too much.
Now I must get back to doing something more up-to-date, such as using the rather interesting XMOS xCORE processors to implement a 12.5MHz ratiometric reciprocal frequency counter purely in software. That’s possible since the have the best hard realtime architecture I’ve seen in decades. Highlights – which enable deterministic timings calculated by the IDE tools before execution – include:
- many 100MIPS cores
- no caches/interrupts
- switching fabric for i/o ports plus inter-core and inter-chip comms
- programming in xC, i.e. C with parallel extensions based on CSP with timing
- FPGA-like i/o ports: SERDES, strobed and master/slave ports, timed input and timed output (4ns resolution), multiple programmable clocks
Great fun, and I don’t know of any other processor with those attributes.