Oh dear! After successfully reading the data fill of a previously used PIC 16F628 last night, the programmer then refused to see the chip! Nothing I did could get the PICkit2 to detect the IC again.
This morning, I found out another device, this time a 16F628A, and successfully wrote and verified a fill to it. The original chip still refuses to be detected. Possibly I killed it faffing about last night trying to find the correct location for it on the ZIF socket, and exposing various pins to the programming HV. I cant rule out an iffy programmer at this stage though.
Next step then is to test the newly programmed chip. The code ive used is for an LCD clock. I'll be using one of the LCD modules I got from Finningley rally, to which ive just added a row of SIL pins. No easy feat, as the damn holes wouldnt clear of old solder. Hopefully, this will prove both the programmer and the LCD!