Rana Systems Elite Series User Manual
Page 179
ELITE SERIES USER MANUAL
THEORY OF OPERATION
The second type of command is the bank select
command, characterized by a write by the Apple
CPU to the address space occupied by the con-
troller ‘S EPROM. The bank select commands are
only enabled when the controller’s EPROM is
switched into the peripheral expansion space.
An LED indicates when drives 3 and 4 (Bank 1)
are selected.
Address to Write
Drives Selected (data ignored)
1 and 2
$C800
3 and 4
$C801
(Writes to other addresses between $C800 and
$CFF7 are also possible but may not be supported
in later card revisions).
Fig. 7-6: Controller Bank Select Addresses
The third type of command is the EPROM switches.
These control whether the EPROM is enabled for
the $C800-CFFF peripheral expansion space. An
LED indicates when the EPROM is switched on.
EPROM Switch
Address to Access
Turn on at $C800-CFFF
$Cn00-cnFF (n = slot #)
Turn off EPROM
$CFF8-CFFF
Fig. 7-7: Controller EPROM Map-In/out Addresses
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