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Conn Pin PIC ID
Description, special abilities
of this port.
JE RB5 A8
JE RB4 A9
JE RB3 A10
J2 RG3 SDA1 (ON I2C SIX-PIN CONNECTOR)
J2 RG2 SCL1 (ON I2C SIX-PIN CONNECTOR)
RF0 PIN_LD1 (LD4)
RF1 PIN_LD2 (LD5)
Table 1. UNO32 I/O map to MX3Ck.
14 SERVO 02.2013
every connector has four power and eight I/O pins.
Figure 2 shows where all of the connectors are on
the MX3cK. (Sometimes the silkscreen is a bit difficult to
To find our Arduino-like MPIDE I/O lines and associate
them with connectors and pins, we need to learn a little
about how the MPIDE does its magic. MPIDE abstracts
any particular board layout such that anyone can make a
board and put their I/O lines wherever it makes the most
There are two files associated with this board
definition: Board_Data.c holds the mapping tables that
define the pinout for a board; Board_Data.h defines any
special relationships these pins have, like being an LED or
a UART or SPI port. These files are located here:
<MPIDE install folder>/hardware/pic32/variants/
Where <MPIDE install folder> is depends on your
system as to where it will be installed. On my OSX system,
for instance, it is in the Applications folder as MPIDE.app.
You would “right-click” on this application and select
Show Package Contents and follow this whole path:
Most of this information can also be found in
Appendix C of the Cerebot_MX3cK_rm.pdf file found at
www.Digilentinc.com. I guess you could say that this is
a “teachable moment;” the manual is your friend!
Now, let’s look at the I/O pins and where they are for
now. Table 1 shows this association.
As you can see, not all of the UNO32 I/O numbers
map to an MX3cK connector. There are some signals that
don’t map to PMOD ports, and two signals that map to
LEDs. You can’t write a sketch on an UNO32 and expect it
to work on an MX3cK.
Whew! That was a bit of an eye-strain to sort out!
You can bet I’ll be referring to it often if I use this board
with the MPIDE.
Well, that’s the end of another Mr. Roboto. Hopefully,
I’ve helped and made someone’s life a little easier. Next
month, I promise I’ll have a Roomba running around the
room controlled by an Arduino or a chipKIT board! As
always, you can contact me at roboto@servomagazine
.com and I’ll do my best to help you. SV