Lp 631 Cpu 1; Description; Lp 631 Cpu - Fresenius Medical Care 4008 E Technical Manual

8.11 P.C.B. LP 631 CPU 1
8.11.1

Description

General information
P.C.B. LP 631 is a part of the safety-critical computer control.
This assembly group represents a complete single-board computer which, in conjunction with
input and output boards and a second computer system, performs the entire control of the
hemodialysis machine.
The use of large-scale integration modules manufactured in CMOS technology results in a high-
capacity and reliable control unit with relatively small-size dimensions.
The P.C.B. comprises the following components:
– 8/16-bit microcontroller 80C188
– BUS logic
– EPROM
– Static RAM
– Nonvolatile RAM
– Serial interface module
– Real-time clock with battery buffering
– Watchdog
– DIP switch arrays
– Status indicator LEDs
– Multifunction PAL
8/16-bit microcontroller 80C188
The 80C188 module, which has been developed from the INTEL 8088 microprocessor, repre-
sents a large-scale integration 16-bit microcontroller in CMOS technology.
The following components are already integrated in the chip:
– Clock generator
– Two independent DMA channels
– Programmable interrupt controller
– Three programmable 16-bit counters/timers
– DRAM refresh controller
– Programmable storage and peripheral equipment chip-select logic
– Programmable wait-state generator
– Local bus controller
Internally, the 80C188 operates with 16 bits, and externally with a multiplexed data-address bus
with a data bus width of 8 bits. In conjunction with the integrated system components, the external
8-bit data bus width permits a simple, yet high-capacity circuit design.
With the exception of the DMA and the DRAM refresh controller, all of the components integrated
in the IC are used during processing of the program.
Fresenius Medical Care 4008 4/09.03 (TM)
8-53