Apple II Language Card

What is an Apple Language Card and how to use it

Compatible with Apple II and Apple II+ that has a maximum of 48KB of RAM inside an address space of 64KB. Inside this address space, the upper 16KB are divided between I/O (4KB) and ROM (12KB).

The card has an Autostart ROM, which take over Apple’s ROM-F8.

There are three independently things you can control: (1) Write-protect or write-enable RAM of the Language Card; (2) select or deselect RAM read; (3) select first or second 4KB bank of RAM.

Second 4KB Bank First 4KB Bank RAM/ROM selection
$C080 [-16256] $C088 [-16248] Select RAM, Write-protected RAM
$C081 [-16255] $C089 [-16247] Deselect RAM read (enable ROM), Two (or more) reads: write enable RAM
$C082 [-16254] $C08A [-16246] Deselect RAM read (enable ROM), Write-protected RAM
$C083 [-16253] $C08B [-16245] Select RAM read, Two (or more) reads: write-enable RAM

From: Apple Language Card: Installation and Operation Manual

Apple II Lang Card memory map

Apple II Lang Card memory map

REF: Apple Language System manual (pdf) local mirror 20200418