Datasheet

chipKIT Max32 Reference Manual
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provide 5V tolerance on those pins, the Max32
contains clamp diodes and current limiting
resistors to protect them from 5V input
voltages.
The fact that all I/O pins are 5V tolerant means
that it is safe to apply 5V logic levels to any
pins on the board without risk of damaging the
PIC32 microcontroller.
The minimum output high voltage of the PIC32
microcontroller is rated at 2.4V when sourcing
12mA of current. When driving a high
impedance input (typical of CMOS logic) the
output high voltage will be close to 3.3V. Some
5V devices will recognize this voltage as a
logic high input, and some won’t. Many 5V
logic devices will work reliably with 3.3V inputs.
Input/Output Connections
The Max32 board provides 83 of the I/O pins
from the PIC32 microcontroller to pins on the
input/output connectors, J3, J4, J5, J7, J8, J9,
and J14.
The PIC32 microcontroller can source or sink a
maximum of 18mA on all digital I/O pins.
However, to keep the output voltage within the
specified voltage range (V
OL
0.4V, V
OH
2.4V)
the pin current must be restricted to +7/-12mA.
The maximum current that can be sourced or
sunk across all I/O pins simultaneously is +/-
200mA. The maximum voltage that can be
applied to any I/O pin is 5.5V. For more
detailed specifications, refer to the
PIC32MX5XX/6XX/7XX Data Sheet available
from the Microchip web site.
Connectors J3, J8, J9, and J14 are 2x8 female
pin header connectors that provide digital I/O
signals. Connector J4 is a 1x8 female pin
header that provides digital I/O signals.
Connectors J5 and J7 are 1x8 female pin
headers that provide analog inputs as well as
digital I/O signals.
Connectors J6 and J15 are two-pin headers
that provide power and ground to shield
boards. J6 provides two pins connected to the
VCC5V0 bus and J15 provides two pins
connected to GND.
Note, that although J6, J8, J9 and J15 are
shown as separate connectors on the
schematic, a single connector part is loaded
across all of them when the board is
manufactured.
On connectors J3 and J14, the outer row
(closer to the board edge) of pins corresponds
to the I/O connector pins on an Arduino Mega
or Mega 2560 board. The inner row of pins
provides access to the extra I/O signals
provided by the PIC32 microcontroller.
The chipKIT/Arduino system uses logical pin
numbers to identify digital I/O pins on the
connectors. The logical pin numbers for the I/O
pins on the Max32 are 0 – 85. These pin
numbers are labeled in the silk screen on the
board.
The analog inputs on connectors J5 and J7 are
also assigned digital pin numbers. Pins A0 –
A7 on connector J5 are digital pins 54 – 61,
and pins A8 – A15 on connector J5 are digital
pins 62 – 69.
Pin numbers 70 – 85 are on the inner rows of
connectors J14 and J3.
Peripheral I/O Functions
The PIC32 microcontroller on the Max32 board
provides a number of peripheral functions. The
following peripherals are provided:
UART port 0: Asynchronous serial port. Pin 0
(RX0), Pin 1 (TX0). These pins are connected
to I/O connector J14 and are also connected to
the FT232R USB serial converter. It is possible
to use these pins to connect to an external
serial device when not using the USB serial
interface. This uses UART1A (U1ARX,
U1ATX) in the PIC32 microcontroller.
UART port 1: Asynchronous serial port. Pin 19
(RX1), Pin 18 (TX1). This uses UART1B
(U1BRX, U1BTX) in the PIC32 microcontroller.