A friend was telling me that at work they had trouble with
CMOS chips. Careful handling, reappraisal of design, change of
suppliers all failed to reduce the failure rate. One day, as all
good stories go, they realised that after ignoring the problem,
it had gone away. Good engineering philosophy dictated a post
mortem but little transpired. Could the wet weather have reduced
static build up? Did chaining workers to benches help? Then one
wag pointed out (I deny even the remotest hint of authorship)
that the charge hand (pause!) no longer worked there. There was
no suggestion of his being discharged, he was a down to earth
chap don’t you know. As it happens, the offending chips were bus
drivers so you would expect to see no failures for ages and then
they would all arrive together.
Has anyone ever tried Tabulating nothink? Not RAM but PROM
nothink. In Nas-sys 3 with the alpha field on, you get all manor
of wierd displays. It only occurs if XROM is linked to a memory
address with no ROM (or pin 24 of it if you bend pins). The
reason is related to indeterminate states on the data bus but
ignore it, don’t send one of your Nascoms back like I did.
(Thanks again to B&L at Kenilworth – mice guys).
NB. This is worth repeating, if you haven’t seen it or forgot:
any Nas-sys command defaults to whatever is in the ARG1 to ARG9
locations which means with regular taks you don’t always have to
repeat the length, width or alpha operands. Subsequent Modify or
Execute commands pick up the same starting address if you omit
their operands, which can be handy to know.
There is a company selling reversible floppy discs and I was
about to buy one when I was distracted by special offers on
normal discs. Most discs are double sided whether they are
guaranteed as such or not. To make flip-floppies, all it needs
is a soft-sectoring hole on ’tother side and a notch for write
protect tabs. I would advise experimentation on older discs, a
card slipped inside the jacket and the use of small sharp
scissors (not a knife) to cut the plastic.