Only the back panel USB, front panel USB, VGA, and PS/2 connectors have overcurrent protection. The Desktop Boards' internal connectors are not overcurrent protected and should connect only to devices inside the computer's chassis, such as fans and internal peripherals. Do not use these connectors to power devices external to the computer's chassis. A fault in the load presented by the external devices could cause damage to the computer, the interconnecting cable, and the external devices themselves.
This section describes the board's connectors. The connectors can be divided into these groups:
Note:
When installing the board in a microATX chassis, make sure that peripheral devices are installed at least 1.5 inches above the main power connector, the diskette drive connector, the IDE connector, and the DIMM sockets.
Back Panel Connectors
The figure below shows the location of the back panel connectors. The back panel connectors are color-coded in compliance with PC 99 recommendations. The figure legend below lists the colors used.
Item
Description
Color
A
PS/2 mouse port
Green
B
PS/2 keyboard port
Purple
C
Serial port A
Teal
D
Parallel port
Burgundy
E
LAN
Black
F
USB ports
Black
G
Audio line in
Light blue
H
Mic in
Pink
I
Audio line out
Lime green
INTEGRATOR'S NOTE:
The back panel audio line out connector is designed to power headphones or amplified speakers only. Poor audio quality occurs if passive (non-amplified) speakers are connected to this output.
Internal I/O Connectors
The internal I/O connectors are divided into the following functional groups:
The figure below shows the location of the audio, power, and hardware control connectors.
Item
Description
A
Front panel audio
B
+12 V power connector (ATX12V)
C
Rear chassis fan
D
Processor fan
E
Main power
F
Front chassis fan
G
Chassis intrusion
Add-in Board and Peripheral Interface Connectors
The figure below shows the location of the add-in board connector and peripheral connectors for the Desktop Board D845PEMY. Note the following considerations for the PCI bus connectors:
All of the PCI bus connectors are bus master capable.
SMBus signals are routed to PCI bus connector 2, enabling PCI bus add-in boards with SMBus support to access sensor data on the Desktop Board. The SMBus signals are as follows:
The SMBus clock line is connected to pin A40
The SMBus data line is connected to pin A41
Item
Description
A
PCI bus connector 3
B
PCI bus connector 2
C
PCI bus connector 1
D
AGP connector
E
Diskette drive
F
Primary IDE
G
Secondary IDE
External I/O Connectors
The figure below shows the location of the external I/O connectors.
Item
Description
A
Serial port B (optional)
B
Auxilary front panel power/sleep LED
C
Front panel
D
Front panel USB
Front Panel Connector
This section describes the functions of the front panel connector. The table below lists the signal names of the front panel connector. The figure below is a connection diagram for the front panel connector.
Hard Drive Activity LED
Pin
Signal
In/Out
Description
1
HD_PWR
Out
Hard disk LED pull-up (750 ohm) to +5 V
3
HAD#
Out
Hard disk active LED
Power LED
Pin
Signal
In/Out
Description
2
HDR_BLNK_GRN
Out
Front panel green LED
4
HDR_BLNK_YEL
Out
Front panel yellow LED
Reset Switch
Pin
Signal
In/Out
Description
5
Ground
Ground
7
FP_RESET#
In
Reset switch
9
+5 V
Out
Power
On/Off Switch
Pin
Signal
In/Out
Description
6
SWITCH_ON#
In
Power switch
8
Ground
Ground
10
No connect
Not connected
Front Panel USB Connector
The figure below is a connection diagram for the front panel USB connector.
INTEGRATOR'S NOTES
The +5 V DC power on the USB connector is fused.
Pins 1, 3, 5, and 7 comprise one USB port.
Pins 2, 4, 6, and 8 comprise one USB port.
Use only a front panel USB connector that conforms to the USB 2.0 specification for high-speed USB devices.
![[D845PEMY Back Panel Connectors]](/design/motherbd/my/pix/my_bpan.gif)
![[D845PEMY Audio Connectors]](/design/motherbd/my/pix/my_audio.gif)
![[D845PEMY Add-in Board And Peripheral Interface Connectors]](/design/motherbd/my/pix/my_addin.gif)
![[D845PEMY External I/O Connector]](/design/motherbd/my/pix/my_extrnl.gif)
![[D845PEMY Front Panel Connector]](/design/motherbd/my/pix/my_fpan.gif)
![[D845PEMY Front Panel USB Connector]](/design/motherbd/my/pix/my_fpan_usb.gif)
