$C083

 

 

— 16253

0011

Selects RAMCard RAM read, BANK 2, and

 

 

write-enables RAMCard RAM if address ac

 

 

cessed twice consecutively

$C088

 

 

—16248

1000

Selects RAMCard RAM read, BANK 1, and

 

 

RAMCard RAM write-protect

$C089

 

 

—16247

1001

Selects Apple on-board ROM read, BANK 1,

 

 

and write-enables RAMCard RAM if address

 

 

accessed twice consecutively

$CO8A

 

 

-16246

1010

Selects Apple on-board ROM read, BANK 1,

 

 

and RAMCard RAM write-protect

$CO8B

 

 

—16245

1011

Selects RAMCard RAM read, BANK 1, and

 

 

write-enables RAMCard RAM if address ac-

 

 

cessed twice consecutively

NOTE: If RAMCard RAM was already in a write-enabled state, only a angle access of a write-enable control address ($C081, $C083, $C089, $C08B) is necessary to remain in a write-enable state until a write- protect control address is accessed. (This state applies immediately following power on.)

Additional Technical Details

The topics in these sections include status bits, the LED Indicators on RAMCard, and RAMCard hardware details.

Status Bits

Whenever a read is performed to any of the control addresses which alter RAMCard functions, the lower four bits of data returned show the status JUST PRIOR to the read.

The four status hits (not to be confused with the bits of the control address) indicate:

BANK SELECT — When BANK I is selected, status bit 0 will be high. When BANK 2 is selected, status hit 0 will be low. This state applies immediately following power on.

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