Technical information

SETTING UP
Adding RAM to the Expansion Interface
Connecting your "no RAM" unit (26-1140) will not affect the total
amount of memory in your system.
Before adding RAM to
your Expansion Interface, you must fill your
TRS-80 with 16K RAM. Then, when you need more memory, you
have it added to the Expansion Interface in blocks of 16K, for a total
of up to 32K in the Interface, or a system total of up to 48K.
Preserve
your Warranty - let Radio shack install and test all
additional
RAM in your Interface. The installation charge is included
in the price
of each additional 16K RAM kit (26-1101).
Here's a memory
map showing the highest memory addresses in the
various possible configurations:
FIRST USER RAM ADDRESS
"4K" TRS-80'S STOP HERE
"16 K"TRS-80'S STOP HERE
FIRST ADDRESS IN
EXPANSION
INTERFACE
"16K" EXPANSION
INTERFACES STOP HERE
"32K" EXPANSION
INTERFACES STOP HERE --
HEX
ADDRESS
DECIMAL
ADDRESS
}
4K
SYSTEM
16K
SYSTEM
32K
SYSTEM
48K
SYSTEM
Figure 8. RAM addresses in the various TRS-80/Expansion Interface systems.
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