Memory Map

Memory Map

The VIC-20's 6502 Microprocessor can directly address 64KB of memory.

1KB Low Memory

$0000-$03ff 1K Low Memory (O/S and Basic working areas).

$0100-$01FF CPU Stack

3KB Expansion Block 1

$0400-$0fff 3K Expansion Block 1

4KB Main RAM

$1000-$1FFF 4KB Main RAM

$1E00-$1FFF Screen Character Memory

8KB Expansion Blocks

$2000-$3FFF 8K Expansion Block 2

$4000-$5FFF 8K Expansion Block 3

$6000-$7FFF 8K Expansion Block 4

I/O Chip Areas

$8000-$8FFF Character ROM

$9000-$900F VIC Chip Registers

$9110-$911F 6522 VIA Chip #1 Registers

$9120-$912F 6522 VIA Chip #2 Registers

$9400-$97FF Color RAM (1K of 4 bit nibbles)

$9800-$9BFF I/O Expansion 2

$9C00-$9FFF I/O Expansion 3

8K Expansion Area Block 5

$A000-$BFFF 8K Expansion Block 5. Often used for ROM. Allows autostart sequence.

ROM Areas

$C000-$CFFF Basic Interpreter ROM

$D000-$FFFF Kernel ROM