Apple Desktop Bus (ADB)
------------------------
One connector is located on the back panel of Power Macintosh computers. It is a 4-pin mini-DIN socket.
Pin Description
--- -----------
1 Data; grounded by an open collector or pulled to +5 V through 470
2 Power on, fed by +5 V through 100 k; connect to pin 4 to turn on
the system
3 +5 V at 500 mA maximum drain; protected by a 1.25-A circuit breaker
4 Ground return
Ethernet
--------
All models of Power Macintosh contain built-in Ethernet. The 9500's offer two types of connection.
One AAUI-15 Ethernet connector
Pin Description Pin Description
--- ----------- --- -----------
1 +5 V 8 +5 V
2 DI+ 9 DO+
3 DI- 10 DO-
4 Ground 11 Ground
5 CI+ 12 No Connection
6 CI- 13 No Connection
7 +5 V 14 +5 V
And One 10Base-T Ethernet connector (NOTE: If both 10BASE-T and AAUI connectors are plugged in, the computer uses the 10BASE-T connector by default.)
The pin configurations for 10BASE-T are as follows:
RJ-45 Connector
-----------------------------
| 1 2 3 4 5 6 7 8 |
| ----------------------- |
| |\\\\ \\\\ \\\\ \\\\ \\\\ \\\\ \\\\ \\\\| |
| | | |
| | | |
| | | |
| ----- ----- |
| | | |
| --- --- |
| | | |
| ------ |
-------------------------------
Contact: Signal:
1 TD+
2 TD-
3 RD+
4 Not Used by 10BASE-T
5 Not Used by 10BASE-T
6 RD-
7 Not Used by 10BASE-T
8 Not Used by 10BASE-T
Serial Ports
------------
The back panel of all Power Macintosh models contain two I/O ports for serial telecommunication data. Both sockets accept 9-pin plugs allowing either port to be independently programmed for asynchronous or synchronous communication formats up to 9600 bps. This includes AppleTalk and the full range of Apple GeoPort protocols.
Pin Name Function
--- ---- --------
1 SCLK(out) Reset pod or get pod attention
2 Sync(in)/SCLK(in) Serial clock from pod (up to 920 Kbit/sec.)
3 TxD- Transmit -
4 Gnd/shield Ground
5 RxD- Receive -
6 TxD+ Transmit +
7 Wakeup/TxHS Wake up CPU or do DMA handshake
8 RxD+ Receive +
9 +5 V Power to pod (350 mA maximum)
SCSI Connection
---------------
The SCSI interface in Power Macintosh computers exists in two forms: an internal 50-pin ribbon connector for internal devices and an external DB-25 connector for external devices.
Pin Number Description Pin Number Description
------------------- ----------- ------------------- -----------
Internal External Internal External
1 7 Ground 2 8 /DATA0*
3 9 Ground 4 21 /DATA1
5 14 Ground 6 22 /DATA2
7 16 Ground 8 10 /DATA3
9 18 Ground 10 23 /DATA4
11 24 Ground 12 11 /DATA5
13 Ground 14 12 /DATA6
15 Ground 16 13 /DATA7
17 Ground 18 20 /DATAP
19 Ground 20 No connection
21 Ground 22 No connection
23 Ground 24 No connection
25 No connection 26 25 TERMPWR
27 Ground 28 No connection
29 Ground 30 No connection
31 Ground 32 17 /ATN
33 Ground 34 No connection
35 Ground 36 6 /BUSY
37 Ground 38 5 /ACK
39 Ground 40 4 /RST
41 Ground 42 2 /MSG
43 Ground 44 19 /SEL
45 Ground 46 15 /C/D
47 Ground 48 1 /REQ
49 Ground 50 3 /I/O
* A slash (/) before a signal name indicates that it is in the low state
when active.
Floppy Disk Drive Connection
----------------------------
All Power Macintosh models contain one internal Apple superDrive floppy disk drive, which supports GCR and MFM formats for 1.44 MB disks.
Pin Signal Description Pin Signal Description
--- ------ ----------- --- ------ -----------
1 GND Ground 11 +5 V +5 V
2 PH0 Phase 0 state control 12 SEL Head select
3 GND Ground 13 +12 V +12 V
4 PH1 Phase 1 state control 14 /ENBL* Drive enable
5 GND Ground 15 +12 V +12 V
6 PH2 Phase 2 state control 16 RD Read data
7 GND Ground 17 +12 V +12 V
8 PH3 Phase 3 register write 18 WR Write data
strobe
9 NC No connection 19 +12 V +12 V
10 /WRREQ Write data request 20 NC No connection
* A slash (/) before a signal name indicates that it is in the low state
when active.
Monitor Support
----------------
The Power Macintosh 9500/120 includes an accelerated display card based on the mach64 graphics accelerator from ATI Technologies, Inc.
Pin Description Pin Description
--- ----------- --- -----------
1 Red ground 9 Blue video signal
2 Red video signal 10 Monitor sense 2
3 Composite synchronization 11 Synchronization ground
4 Monitor sense 0 12 Vertical synchronization
5 Green video signal 13 Blue ground
6 Green ground 14 Horizontal synchronization ground
7 Monitor sense 1 15 Horizontal synchronization
8 No connection
The Power Macintosh 9500/132 requires a third-party (non-Apple) graphics accelerator for display support.
Sound I/O
---------
All Power Macintosh computers contain external stereo 3.5mm jacks for sound I/O, connected through amplifiers to the AWAC chip.
Panel label Description
----------- -----------
Audio In 8 k impedance, 2 V rms maximum, 22.5 dB gain available
Audio Line Out 37 impedance, 0.9 V rms maximum, attenuated -22,5 dB
(crosstalk degrades from -80 to -32 dB when the audio
output is connectedto 32 headphones)