One trick to use the Wisp628 to program those with Vdd-before-Vpp
like 12F629/12F675 and maybe 16F628A/16F648A.

The blank chip does not have code inside so that the chip will not
running and no interference with PGC/PGD will happen. Therefore
erasing the chip with command like "xwisp2w port 2 erase" and
then programming the chip will be okay.

Of course this may or may not work since the erase command may
be interfered by the code running as well in theory. However this
trick works for me so far.

Wouter's dongle may be a better solution for this kind of chips. Still
I think the ultimate solution (for off-line programming) is to change
the Wisp628 design and control the Vdd-target.


Regards,
Xiaofan

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