Apple Macintosh portable Processor-Direct Slot (PPDS)

D0-D15

Unbuffered data bus, bits 0 through 15

A1-A23

Unbuffered address bus, bits 1 through 23

16M

16 MHz clock

/EXT.DTACK

External data transfer acknowledge. This signal is an input to the processor logic glue. Assertion delays external generation of the /DTACK signal.

E

E(enable) clock

/BERR

Bus error signal generated whenever /AS remains low for more than about 250 us.

/IPL0-/IPL2

Input priority level lines 0 through 2.

/SYS.RST

Initiates a system reset.

/SYS.PWR

A signal from the Power Manager indicated that associated circuits should tri-state their outputs and go inte idle state; /SYS.PWR is pulled high (deasserted) during sleep state.

/AS

Address strobe

/UDS

Upper data strobe

/LDS

Lower data strobe

R/W

Defines bus transfer as read or write signal

/DTACK

Data transfer acknowledge

/DELAY.CS

Indicates that a wait state is inserted into the current memory cycle and that you can delay a CS.

/BG

Bus grant

/BGACK

Bus grant acknowledge

/BR

Bus request

/VMA

Valid memory access

/VPA

Valid peripheral address

FC0-FC2

Function code lines 0 through 2

+5/0V

Provides +5V when the system is running normally and 0V when the system is in sleep mode.

+5/3.7V

Provides +5V when the system is running normally and 3.7V when the system is in sleep mode.