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Hi - I am new to pic programming and am working my way up the learning
curve. I bought a Velleman k8048 programmer which has some on-board
leds and switches for demonstrating simple introductory programs.
This is an excellent and cheap way of getting into pic programming
from a cold start. Very quickly I progressed to my own project board
with other I/O attachments, and immediately ran into a problem. I
discovered that if any of the portb pins on the pic16f627 (other than
those used for programming) is high during programming, the programmer
simply will not work (or to put it another way - the pic will not
program).

This initially caused a load of trouble since I could not find any
reference to the requirement that pb pins should be low to enable
programming in the pic data sheet, and I only discovered the solution
(switch off the supply to the peripherals during programming) by trial
and error.

I am still perplexed by this, and would appreciate comments. I notice
that the pb inputs on the Velleman board have pull-down resistors and
switches to Vdd, so I assume that this is normal behaviour...

AND.... a programming question. Is there any way of reading data
bytes from the program memory of a pic ? I know about RETLW, but it
is very clumsy compared with what I am used to. I want to use the
MPASM directive DA to insert ASCII text bytes into the assembled code,
and then read them out during execution to print messages on a LCD screen.

Andrew

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