From: Don Kuenz <mail@crcomp.net>
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Date: Sun, 15 Nov 2020 16:17:21 -0800
Subject: [PIC] An In-Circuit Serial Programmer application
Thread-Topic: [PIC] An In-Circuit Serial Programmer application
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=20
>> Don wrote:
>>> This project shows how to implement an In-Circuit Serial
>>> Programmer application. It utilizes the ICSP's 5 VDC
>>> (Vdd) pin to toggle the PIC microcontroller between
>>> application mode and programming mode.
>>>
>>> https://crcomp.net/icsp/index.php

> Chris wrote:
>> Nice, but why not just use two Jumpers or a DPDT switch rather than add
>> additional silicon?
>> My preference with the more recent PIC's is to use PPS to assign the USA=
RT
>> to those pins.
>> I then use the PICKit as a terminal for debugging as well as a Programme=
r.
>> The serial interface may even have a use in the target application.
>> Have the serial interface use the same pin assignments as the ICSP and y=
ou
>> have a nice 'Plug and Play' programming/debugging/communications port.

Chris wrote:
> P.S. - It also works well with a Bootloader.
> use the ICSP interface to install the TinyBootloader or an equivalent wit=
h
> the ICSP Dat and Clk lines set at the Rx and Tx lines and you have a nice
> development device with Programming, Debugging and Communications all
> achieved via a USB/Serial adapter - Great to hand out to students or use
> for casual experimenting as well as in target applications.

There's four good reasons (or at least three and a half) for me to use=20
additional silicon. Let's start with the half reason. If you look=20
closely at Figure 4 you see a blue DIP switch near the top, middle. It's
a drag to flip those switches each time. A mouse click is so much=20
easier.
    There's also a dearth of ICSP applications available on the Inet,
probably for a very good reason. The wide, inviting, easy route with old
MCUs is to simply dedicate RB6 and RB7 to ICSP. The third reason is my
application allows all 8 bits of RB to be used.
    The final reason is actually the best. It motivated you to talk
about another way. It's time for me to step up to an MCU with a UART.

Danke,

--=20
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

--=20
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