Iv-6. Memory Map; Memory-Map; Dip-Sw Location - Tandy 1400LT Service Manual

IV-6. MEMORY MAP
Figure 4-7 Memory-Map shows the location on the board of the IC and the corresponding memory Column-Address
Strobe ( CASO
,
CASl
,
CAS2 )
-~~
FFFFFH
FCOOOH
DCOOOH
COOOOH
BCOOOH
BBOOOH
AOOOOH
7FFFFH
40000H
OOOOOH
I P L
,
ROMBIOS
(40000H -9FFFFH and DCOOOH -FBFFFH addresses are enabled or disabled by DIP switch (DS1)).
-
CAS2 SIGNAL
RAM
(
I C 3 0 1 , I C 3 0 3
)
(
D I P SWITCH SELECT
)
EXPANSION
ROM
AREA
NOT USED
VIDEO RAM
NOT USED
RAM
(
I C 3 0 1 , I C 3 0 3
RAM
(
IC300
.
I C 3 0 2
RAM (
I C 4 3 , I C 4 4
)
Figure 4-7. Memory-Map
Figure 4-9 shows the switch settings and description.
-
CAS2 SIGNAL
-
CASl SIGNAL
-
CASO SIGNAL
Function Description
InternaVExternal use Internal use
address 4000:0-9000:FFFF External use
sw
2 InternaVExternal use Internal use
Figure 4-8. DIP-SW Location Figure 4-9. DIP-SW
4-7