Citadel TouchStar TS3000, Руководство пользователя

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TS3000/TS4000 TouchStar Systems User Manual
System Memory Configuration
The TouchStar system memory can be configured with 4, 8, 12,
or 16 MB of dynamic random access memory (DRAM). The
DRAM is implemented in two SIMMs (single in-line memory
modules) that plug in to sockets on the motherboard. Each
SIMM socket can hold either a single- or dual-bank SIMM
containing 1, 2, 4, 8 or 16 MB. All system memory above 1MB is
accessible as extended memory. Table 1 illustrates some possible
DRAM combinations installed in the two SIMM sockets.
Total RAM Socket 1 Socket 2
4MB 4 0
8MB 4 4
8MB 8 0
12MB 8 4
16MB 8 8
16MB 16 0
Table 1. System Memory SIMM Combinations
CMOS RAM
On-board feature configuration information is stored in AT-style
CMOS random access memory (RAM). The TouchStar integrates
128 bytes of CMOS RAM and real time clock (RTC) into the
main system controller. The system’s CMOS RAM is accessed
via I/O locations 0070
H
- 0071
H
. Table 2 shows the configuration
of the system’s available memory.
Location Description
0 - 13 Real-time clock (RTC) functions
14 - 127 General low-power static RAM
Table 2. CMOS RAM Memory Allocation
Multiple memory locations in the TouchStar are reserved for
storing BIOS-dependent configuration information. To access
CMOS RAM, the index address (0 to 7F
H
) is output to port 70
H
,
and the data is then read or written at port 71
H
. Interrupts
should be inhibited while the entire port 70
H
/71
H
sequence is
B - SYSTEM REFERENCE