D20/D200 Technical Overview
GE Grid Solutions
32
PRPI-019-3.00-10
GE Information
Item
Description
Communications
•
Two HDLC ports for link to peripheral modules
•
The D20ME has seven programmable RS-232 serial ports for communications to SCADA
master, satellite RTUs and IEDs. The D20ME II has seven programmable serial ports,
any combination of RS-232 and RS-485.
•
38,400 kbps on all 7 ports, all running half duplex & 100% utilization (D20ME and D20ME
II)
•
9600 baud, RS-232 maintenance port (D20ME and D20ME II)
•
Support leased/dial-up telephone lines, modems, 900 MHz radio, trunked radio, spread
spectrum radio, microwave, and fiber optic communications.
Power Requirements
•
Power consumption: 3.5 W typical, 5 W max.
Physical
•
LED indications: Run/Halt and System Fail
2.2.3 Firmware
The D20ME contains two types of firmware: BootROM and flash applications. BootROM
contains the software needed to start up a D20 and diagnostic applications. Application software
consists of a base system that includes the operating system, hardware-dependent software, and
applications that are modular and hardware-independent so they can run on multiple platforms
(D20, D25 and iBOX, for example).
2.2.3.1 BootROM
BootROM firmware is stored on an EPROM chip. The following types of programs are stored as
BootROM firmware:
•
Operating system
•
Boot-up (reset) code
•
Device drivers
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IRQ controller initialization
•
Interrupt service procedures
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Monitor functions
•
Root process
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Watchdog task
Operating System
The D20ME operating system is pSOS
®
. pSOS is a real-time, multi-tasking operating system
kernel, with the following features:
•
Integrated, multi-tasking with a structured efficient supervisory layer
•
Priority scheduling of processes in coordination with other tasks. User applications are
partitioned into sets of processes