William System 11 Memory Map

U25 - SRAM

$0000-$07FF

U10 - 6821 PIA

$2100-$2101 - Sound Select Outputs
$2102-$2103 - Solenoid Drives (9-16)

U28 - 74LS374 Latch

$2200 - Solenoid Drives (1-8)

U54 - 6821 PIA

$2400-$2401 - Lamp Matrix Drives
$2402-$2403 - Lamp Matrix Strobes

U51 - 6821 PIA

$2800-$2801 - Display Strobes
$2802-$2803 - Display Segments

U41 - 6821 PIA

$2C00-$2C01 - Display Data A
$2C02-$2C03 - Display Data B

U38 - 6821 PIA

$3000-$3001 - Switch Matrix Inputs
$3002-$3003 - Switch Matrix Drives

U42 - 6821 PIA

$3400-$3401 - Display Data C
$3402-$3403 - Widget I/O

U26 - ROM 2

$4000-$7FFF

U27 - ROM 1

$8000-$FFFF