LPC11U37 is footprint and pin superset of the old
stamp ®. The board can be used
with 5V TTL signals. It has a total of 40 IO pins available.
BASIC or C programs can be downloaded using the builtin USB
connector. MakeItC and BASICtools use the USB serial connection of the
board. You can load mBed programs by shorting the ATN and GND pins (3 and
4 of the stamp arrangement) which then bring the device up as a disk drive that
you can overlay the firmware.bin file. It can be ordered with an optional
JTAG/SW connector so that it can use Keil, IAR, MCUxpresso or other tools.
The board can also be ordered as a JTAG/SW debugger that can connect to other
Digital IO connections
Below is a diagram of the
pins, with the USB connector shown at the top. The diagram on the right ONLY
applies to the handful of alpha test boards shipped via
eBay or Kickstarter beta testers.
The NXP pins P0.1-31 shown
as 1-31 and P1.0-31 as 32-63 below in red. For convenience the pins can be
refered to as SP0-39 as stamp pins by using the definitions in STAMP_PINS.bas and STAMP_PINS.h (shown
in black and green below).
There is an A/D converter
with an 8 input analog multiplexor. After power on these pins are inputs, when a
calls for an AD input they are converted to analog.
Special purpose pins
RESET pin starts the ARM program if the
ATN/SP18 (P0.1) pin is high. If you use ATN/SP18 P0.1 as an input you MUST
make sure it is in the high state when RESET is asserted, otherwise your program
will NOT start. RESET can also be defined as a IO, though
you must enable it with a specific call. On power on the RESET pin has
an internal pullup and must be high during this time or your program will not
SOUT and SIN (SP17-18) are configured
as inputs on reset. They are converted to TTL serial lines (positive true)
is set. The USB serial connection is
TXD(0), RXD(0) and configured by default
Pins are configured as digital inputs on power on, SP23 and SP24 are
open collector pins, which can be used as IOs or dedicated I2C
pins. The Serial Wire debug pins (SP30 SP35) are converted to inputs by the initial firmware,
but can be used by SW/JTAG pins by other tools such as Keil, IAR and
The LPC11U37 supports a number of
dedicated functions. Those include 1 UARTs, 2 SSP/SPI, 1 I2C, I2S, 2 multi-channel
PWMs,timer counter capture and match.
The internal 24 stamp pins are on a 0.1" DIP
spacing with a 0.6" width. An additional 24 pins are also 0.1" space with a 0.8"