WD29C020C's erase still works ;)
To note that i disabled udelay.c's recalibration stuff for now (see the
timings in the log, weird...) - I only use the serprog driver (that
implements delays on the programmer device) on this machine so not a real
problem for me but mysterious.
command line used was:
./flashrom -p serprog:/dev/ttyUSB0:1500000 -EV > erase_wd29c020c.log
Programmer device used was my self built ATMega644 USB programmer with
self-written firmware implementing the serprog protocol.