Mark Rages wrote:
>>               Empty   Full
>> USBProg (USB)   2.5   12.2
>> USBProg (ser)   2.1   11.8
>> ProProg         6.4   16.5
>> EasyProg        4.4   14.3
>>
>
> You could save time by skipping one of the readback passes, as
> two-voltage verification is not specified for the 16F676.  This is
> required for OTP and legacy parts like the 16F84.

I have recently added the -VDD command line option on PIC_PROG.  That tells
the program to use that single Vdd level for all operations, which also
causes it to do only one verify pass.  A single Vdd level could also be
specified in the PICPRG.ENV file for that PIC.

However you're not going to save much since the bulk of the time is spent
writing, not reading.  The 16F676 requires 8mS/word, which is the limiting
factor in this case.  This can also be seen from the large difference
between the full and empty times.  The only difference between them is that
the HEX file specified the erased value in the empty case and random values
in the full case.  The programming algorithm therefore skipped all ordinary
program memory and EEPROM writes in the empty case.

The absolute minimum time to write to all the program memory and EEPROM of a
16F676 is (1024 prog mem words + 128 EEPROM bytes) x 8mS = 9.2 seconds.
Note that my fastest case is only 2.6 seconds more than that.  The time to
start the program, inquire the programmer firmware capabilities, determine
the target chip type, perform the Vdd and Vpp manipulations with settling
time, read the calibration constants and restore them after erasing, do the
bulk erase, round the 8mS wait time up to the nearest whole internal clock
ticks, and perform two full readbacks of the chip all come out of the
remaining 2.6 seconds.  You just aren't going to save a lot of time
eliminating one of the readback passes in this case.


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