Atari 800

CHIP NAME
POKEY
PIA
FUNCTION
Keyboard scan and control
Serial communications port (bidirecti mal)
Pot scan (digitizes position of 8 indepen~~ n t pots)
Audio generation (4 channels)
Timers
IRQ (maskable interrupt) control from peripher? : s
Random number
generator
Controller (Joystick) jacks read or write
Peripheral control and interrupt lines
IRQ (maskable) interrupt control from peripherals
Section II describes the hardware in some detail, including the
various graphics modes. Section III lists the hardware registers one at a
time, describing what each bit is used for. It is organized by functional
groups (interrupts, graphics, audio, etc.). Section IV contains a sample
display program. Section V contains various figures and block diagrams of
the system. Sections VI and VII list the hardware registers in address
order and alphabetical order. Section VII includes hex and decimal
addresses, the OS shadow registers and the page numbers where more infor-
mation can be found.
1.2