52 November 2017
The new ME Labs Advanced D-Stick you see in Photo
1 is based on a Microchip PIC18F47K40. If you recall, we
discussed the Advanced D-Stick’s predecessor (which was
built around a PIC16F1937) in a previous Design Cycle.
The D-Stick concept hasn’t changed. However, the new
PIC18 D-Stick is a much more capable development
Like the first D-Stick, the new PIC18 D-Stick is
equipped with an onboard programming system that does
not require an external PIC programmer. Power for the
Advanced D-Stick is obtained via its integral USB portal.
The I/O and power pinout of the PIC18 D-Stick match the
layout of the PIC18F47K40. This pin-for-pin similarity allows
us to plug the D-Stick into the same standard 40-pin socket
that would normally support the PIC18F47K40 itself.
The ability to place the Advanced D-Stick in a
spot normally reserved for a PIC18F47K40 allows us
to plug our PIC18 based D-Stick into a Microchip
Explorer 8 eight-bit development board. I’ve done
just that in Photo 2. The Explorer 8 is a self-contained development system that is aimed at
Microchip’s full line of eight-bit PICs. Since the new
D-Stick is powered and fed from its USB connector,
we must defang the Explorer 8’s power subsystem.
We’ll do this by strategically placing and removing
Explorer 8 jumpers.
The location of these various jumpers can be
seen in Figure 1. Our goal is to isolate the Explorer
8 voltage regulators that are fed externally to
prevent forcing + 5 volts from the D-Stick into the
voltage regulator outputs. We’ll start by removing
jumpers J2 and J24, which are represented by items
16 and 19 in Figure 1. As you can see in Schematic
1, we’ve isolated the Explorer 8’s + 5 volt and + 3. 3
volt voltage regulators.
Up Close and Personal with the
ME Labs Advanced PIC18 D-Stick
■ BY FRED EADY
I have this thing for microcontroller development tools. One of my very first PIC
microcontroller projects was a home-brewed PIC programmer that was based on a
garage-brewed PIC assembler. As I get older, it seems that the tools just get better.
Microchip keeps pumping out the microcontrollers, and the development tools
that support them follow. In this installment, we will mount the latest ME Labs
development tool on the latest Microchip development tool, and write some code
using the latest version of the ME Labs PBP BASIC compiler.
THE DESIGN CYCLE
■ PHOTO 1. This is a self-contained PIC18F47K40
development platform, which is powered by its USB
connection. The Advanced PIC18F47K40 D-Stick can be
programmed with anything that generates a PIC
microcontroller-compatible hex file.
■ PHOTO 2. The Explorer 8 takes to the Advanced D-Stick like a
duck to water. All we have to do is make sure the Explorer 8’s
power supplies don’t clash with the D-Stick’s power system.