LPC2157_2158 NXP Semiconductors, LPC2157_2158 Datasheet - Page 27

• Manufacturer Part Number: LPC2157_2158
• Description: The LPC2157/2158 is a multi-chip module consisting of a LPC2138/2148 single-chipmicrocontroller combined with a PCF8576D Universal LCD driver in a low-cost 100-pinpackage
• Manufacturer: NXP Semiconductors

NXP Semiconductors
Table 4.
LPC2157_2158_2
Product data sheet
Number of
Backplanes
4
3
2
1
Selection of display configurations
6.20.2 RealMonitor
6.21.1 General description
6.21.2 Functional description
6.21.3 LCD bias voltages
6.21 LCD driver
Segments
128
96
64
32
The JTAG clock (TCK) must be slower than
interface to operate.
RealMonitor is a configurable software module, developed by ARM Inc., which enables
real-time debug. It is a lightweight debug monitor that runs in the background while users
debug their foreground application. It communicates with the host using the DCC, which is
present in the EmbeddedICE logic. The LPC2157/2158 contain a specific configuration of
RealMonitor software programmed into the on-chip flash memory.
The LCD segment driver in the LPC2157/2158 can interface to most LCDs using low
multiplex rates. It generates the drive signals for static or multiplexed LCDs containing up
to four backplanes and up to 32 segments. The LCD controller communicates to a host
using the I
LCD driver are available on the LPC2157/2158 providing system flexibility.
Communication overhead to manage the display is minimized by an on-chip display RAM
with auto-increment addressing, hardware subaddressing, and display memory switching
(static and duplex drive modes). Please refer to PCF8576D data sheet for electrical data.
The LCD controller is a versatile peripheral device designed to interface microcontrollers
to a wide variety of LCDs. It can directly drive any static or multiplexed LCD containing up
to four backplanes and up to 32 segments. The display configurations possible with the
LCD controller depend on the number of active backplane outputs required. A selection of
display configurations is shown in
in a typical system.
The microcontroller communicates to the LCD controller using the I
appropriate biasing voltages for the multiplexed LCD waveforms are generated internally.
The only other connections required to complete the system are to the power supplies
(V
LCD biasing voltages are obtained from an internal voltage divider consisting of three
series resistors connected between V
compensated externally via the supply to pin V
multiplexing of the LCD based on programmable configurations.
DD(LCD)
, V
7-segments numeric
Digits
16
12
8
4
2
C-bus. The I
SS
and V
LCD
Rev. 02 — 9 February 2009
2
) and the LCD panel chosen for the application.
C-bus clock and data signals for both the microcontroller and the
Indicator
symbols
16
12
8
4
Table
LCD
4. All of these configurations can be implemented
and V
14-segments alphanumeric
Characters
8
6
4
2
1
6
Single-chip 16-bit/32-bit microcontrollers
of the CPU clock (CCLK) for the JTAG
LCD
SS
. The LCD voltage can be temperature
. A voltage selector drives the
Indicator
symbols
16
12
8
4
LPC2157/2158
2
C-bus.The
© NXP B.V. 2009. All rights reserved.
Dot matrix
128
96
64
32
27 of 45