NXP Semiconductors
UM10817
OM13503, PCA8539 demo board
UM10817
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© NXP B.V. 2014. All rights reserved.
User manual
Rev. 1 — 3 September 2014
6 of 13
2.3 Jumpers
The board contains a number of jumpers. Below they are listed, along with their
functionality.
•
JP1 through JP6
: They are all used to select either the I²C-bus interface, or the SPI
interface. They need to be all in the same position. The silk screen indicates which
position to use for a given interface. Refer also to the datasheet.
•
JP7
: This jumper connects the V
LCDOUT
and V
LCDSENSE
to the V
LCDIN
pin of the
PCA8539. It must be placed if the internal voltage generation is used.
•
JP8
: This jumper connects the V
LCDIN
pin of the LCD driver to the external voltage
VLCD_IN connected to connector P2. However, if also the internal voltage generator
is enabled, this can cause damage to the LCD driver.
•
JP9
: This jumper may not have been soldered into the board during manufacturing.
Instead, a 0 Ω resistor (R2) is mounted, in parallel with this jumper. Removing the
0 Ω resistor and mounting the jumper makes it easy to insert a current meter and
measure the current consumption to the V
DD
pins of the PCA8539. After
measurements, a jumper header can be inserted.
2.4 Use of internal/external oscillator
The PCA8539 offers the option of using the internal oscillator or to use an external
oscillator. Resistor jumper R1 (0 Ω) connects the OSC pin to V
SS
for selecting the internal
oscillator. If an external oscillator signal is desired, R1 must be removed and R12 must
be mounted. If the internal oscillator is used, the oscillator signal is available at connector
pin “CLK”. If an external oscillator signal is used, this can be supplied to the LCD driver
using this connector “CLK”.
2.5 Connectors
Besides the previously mentioned connectors, connector P3 contains the I²C and SPI
signals, along with V
SS
and a reset signal. This connector can be used to connect the
baseboard to another application/microcontroller. In that case, the LPCXpresso board
must be removed.
2.6 LPCXpresso
LPCXpresso is a low-cost development platform available from NXP. The software
consists of an enhanced, Eclipse-based IDE, a GNU C compiler, linker, libraries, and an
enhanced GDB debugger. The hardware consists of the LPCXpresso development board
which has an LPC-Link debug interface and an NXP LPC ARM-based microcontroller
target. LPCXpresso is an end-to-end solution enabling embedded engineers to develop
their applications from initial evaluation to final production.
The LPCXpresso IDE is based on the popular Eclipse development platform and
includes several LPC-specific enhancements. It is an industry-standard GNU tool chain
with an optimized C library that gives engineers all the tools necessary to develop high-
quality software solutions quickly and cost-effectively. The C programming environment
includes professional-level features. There is syntax coloring, source formatting, function
folding, on- and offline help, and extensive project management automation.
The LPCXpresso target board, jointly developed by NXP, Code Red Technologies, and
Embedded Artists, includes an integrated JTAG debugger (LPC-Link), so there is no
need for a separate JTAG debug probe. The target portion of the board can connect to
