Technical Supplement
S- 6
The QSM allows the real-time clock to communicate to the QSM by
connecting the MISO and MOSI lines. The signals from the QSM are tied to
the 5-volt power supply through resistors.
The SCI submodule communicates with the blood pressure module in an
EIA -232 format at the 5-volt level.
Analog to Digital Converter Module
The A/D Converter module has eight analog inputs that can be converted to
digital representations. A voltage divider is used to reduce the input voltages
to a value that is within the 0-5 volt range of the A/D converter.
System Integration Module
The system integration module provides configuration control, system clock
control, internal bus transfer control, and interrupt handling control. Port E
uses the HC16 bus signals for bit positions 2 through 7 and discrete input
signals for bit positions 0 and 1. Port F can be configured to be either discrete
signals or interrupt requests.
S4.2.1.2. Peripheral and Support ICs
The peripheral and support ICs for the U3 microprocessor include program
memory chip U10, data and variable memory U13, trend memory U4, serial
EEPROM U7, real-time clock U12, Arcnet controller U8, digital-to-analog
converter U5, power on reset/watchdog timer U21, and the display buttons.
Program memory — U10 contains the program code in a 512K x 16
EPROM. The UIF uses chip select CSBOOT to select the EPROM.
Data and variable memory — U13 uses a scratchpad memory to retain
variables and data during operation. The UIF uses chip select CS0 to select
the 128K x 16 SRAM.
Trend memory — Trend data is retained in parallel EEPROM U4. The 8K x
8 chip will retain data when the N -3100 is turned off. It is selected by CS3
(device select) and CS4 (write enable).
Serial EEPROM — U7 contains instrument configuration, limit data, and
the Error Log. It is accessed by the QSPI serial data line and enabled by
PSC1 chip select.
Real-Time Clock — U12 provides a time sense for the UIF/Power Supply. It
is powered while the unit is off by the lithium batteries. It is accessed by the
WSQI serial data line and is enabled by PSC2 chip select.
Arcnet controller — U8 is used to implement the communication bus
protocol. It is a memory-mapped device that controls all the Stackbus
communications.
DAC — U5 is used to control speaker volume. It is an 8-bit, memory-mapped
device and is enabled by chip select CS5.
