Difference between revisions of "Super I/O"

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(Finnaly added that image, a Super I/O board from a DVT4)
 
(11 intermediate revisions by 3 users not shown)
Line 1: Line 1:
−
The Super I/O board is a feature of [[Development Kits]]. The board is build around a SMSC LPC47M157 chip ([https://drive.google.com/uc?export=download&id=0BxOesalXbGtOanoxenlqQUh6Y0k Datasheet])
+
The Super I/O board is a feature of some [[Development Kits]]. The board is build around a SMSC LPC47M157 chip ([https://drive.google.com/uc?export=download&id=0BxOesalXbGtOanoxenlqQUh6Y0k Datasheet]) and interfaces with the Xbox via a ribbon cable connected to the [[LPC Debug Port]].
 +
 
 +
[[File:SerialIOBoard.jpeg|400px|thumb|right|Super I/O board from a DVT4]]
  
 
The board provides the following ports:
 
The board provides the following ports:
Line 12: Line 14:
 
* Flash-ROM / BIOS (like modchips, replaces onboard kernel?){{citation needed}}
 
* Flash-ROM / BIOS (like modchips, replaces onboard kernel?){{citation needed}}
  
−
[http://codeasm.com/xbox/images/dvt4/SL734874.JPG Picture of the board]{{FIXME|reason=Contact codeasm, he said he'll search for the non-watermarked pic and put it under a good license}}
+
== Schematic ==
 +
Its a four layer board, layers 2 and 3 are filled on the entire board, probably ground and power planes.
 +
north, or up in the next tables is up as written the layer numbers and silkscreen common direction.
 +
The folowing main parts are populated on the board:
 +
{| class="wikitable"
 +
!| total
 +
! Labels
 +
! Description
 +
|-
 +
|1
 +
| U1
 +
| SMSC LPC47M157-NC (1996 )
 +
|-
 +
| 0
 +
| U2
 +
| unpopulated DIP24 MCU(?)
 +
|-
 +
|1
 +
| U3
 +
| MAX223EAI (0104, first week 2004?)
 +
|-
 +
|1
 +
|Y2
 +
|CMX-309FB B (14.3181Mhz  standard Clock Oscillator )
 +
|-
 +
|1
 +
|J7
 +
|AMP rs232 Male connector
 +
|-
 +
|1
 +
|J9
 +
|16 pins male header (LPC bus)
 +
|-
 +
|5
 +
|R1,R7,R10,R11,R12
 +
|10Kohm smd resistor
 +
|-
 +
|7
 +
|C10,C12,C13,C16,C17,C36,C37
 +
|Bigger, probably NOT all the same caps
 +
|-
 +
|17
 +
|C1,C2,C9,C15,C1?(8?),C21,C22,C23,C24,C25,C26,C28,C31,C32,C33,C34,C35
 +
|Smaller, also, asuming not all the same
 +
|}
 +
 
 +
The connections in the following tables are checked with the continuity test on a VOM(Multimeter).
 +
but for now here are the listings of wich pin goes where:
 +
 
 +
=== U3 MAX223EAI [https://datasheets.maximintegrated.com/en/ds/MAX220-MAX249.pdf] ===
 +
 
 +
{| class="wikitable"
 +
!| Pin
 +
! Name
 +
! Type
 +
! Description
 +
! Termination(s)
 +
! Notes
 +
|-
 +
| 1
 +
| T3OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 2
 +
| T1OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 3
 +
| T2OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 4
 +
| R2IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 5
 +
| R2OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 6
 +
| T2IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 7
 +
| T1IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 8
 +
| R1OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 9
 +
| R1IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 10
 +
| GND
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 11
 +
| VCC
 +
| Power
 +
| 5V supply voltage
 +
| J9 6
 +
|
 +
|-
 +
| 12
 +
| C1+
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 13
 +
| V+
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 14
 +
| C1-
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 15
 +
| T4OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 16
 +
| R3IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 17
 +
| R3OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 18
 +
| SHDN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 19
 +
| EN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 20
 +
| R4IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 21
 +
| R4OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 22
 +
| T4IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 23
 +
| T3IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 24
 +
| R5OUT
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 25
 +
| R5IN
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 26
 +
| V-
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 27
 +
| C2-
 +
|
 +
|
 +
|
 +
|
 +
|-
 +
| 28
 +
| C2+
 +
|
 +
|
 +
|
 +
|
 +
|}
 +
 
 +
=== U1 SMsC LPC ic ===
 +
 
 +
Still lots to fill out here, but all connections required for kernel debugging via null-modem cable tied to TX/RX/GND have been accounted for.
 +
 
 +
{| class="wikitable"
 +
!| Pin
 +
! Name
 +
! Type
 +
! Description
 +
! Termination(s)
 +
! Notes
 +
|-
 +
| 6
 +
| CLKI32
 +
| Input
 +
| 32.768kHz trickle clock input
 +
| GND (C17)
 +
| Disabled via GND
 +
|-
 +
| 7
 +
| VSS
 +
| Power
 +
| Ground
 +
| GND (C17)
 +
|
 +
|-
 +
| 18
 +
| VTR
 +
| Power
 +
| 3.3V standby voltage
 +
| C17 bypass to 3.3V
 +
| Connected to VCC because no wakeup functionality is required
 +
|-
 +
| 19
 +
| CLOCKI
 +
| Input
 +
| 14.318MHz clock input
 +
| Y2 3
 +
|
 +
|-
 +
| 20
 +
| LAD0
 +
| I/O
 +
| LPC address/data bus
 +
| J9 11
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 21
 +
| LAD1
 +
| I/O
 +
| LPC address/data bus
 +
| J9 10
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 22
 +
| LAD2
 +
| I/O
 +
| LPC address/data bus
 +
| J9 8
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 23
 +
| LAD3
 +
| I/O
 +
| LPC address/data bus
 +
| J9 7
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 24
 +
| LFRAME#
 +
| Input
 +
| Frame signal
 +
| J9 3
 +
| Indicates start of a new cycle and termination of broken cycle.
 +
|-
 +
| 26
 +
| PCI_RESET#
 +
| Input
 +
| PCI reset
 +
| J9 5
 +
| Used as LPC interface reset.
 +
|-
 +
| 27
 +
| LPCPD#
 +
| Input
 +
| Power down signal
 +
| R7 (10k) pull-up to 3.3V
 +
| Indicates that it should prepare for power to be shut down on the LPC interface. Tied high relying on PCI_RESET to do its job.
 +
|-
 +
| 29
 +
| PCI_CLK
 +
| Input
 +
| PCI clock
 +
| J9 1
 +
|
 +
|-
 +
| 30
 +
| SER_IRQ
 +
| Output
 +
| Serial interrupt requests
 +
| J9 16
 +
| Provides a serial interrupt request line for mouse/keyboard implementations of the IO board.
 +
|-
 +
| 31
 +
| VSS
 +
| Power
 +
| Ground
 +
| GND
 +
|
 +
|-
 +
| 32
 +
| GP10/J1B1
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 33
 +
| GP11/J1B2
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 34
 +
| GP12/J2B1
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 37
 +
| GP15/J1Y
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 38
 +
| GP16/J2X
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 39
 +
| GP17/J2Y
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 40
 +
| AVSS
 +
| Power
 +
| Analog ground
 +
| GND
 +
|
 +
|-
 +
| 42
 +
| GP21/P16/nDS1
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 44
 +
| VREF
 +
| Power
 +
| 3.3V reference voltage
 +
| C2 bypass to 3.3V
 +
| 5V or 3.3V used for the game port logic
 +
|-
 +
| 45
 +
| GP24/SYSOPT
 +
|
 +
|
 +
| R1 (10k) pull-down to GND
 +
| Set the configuration base I/O address of 0x2E (R2 would be a pullup to 3.3V with a different configuration address)
 +
|-
 +
| 47
 +
| GP26/MIDI_OUT
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 49
 +
| GP61/LED2
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 51
 +
| GP30/FAN_TACH2
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 53
 +
| VCC
 +
| Power
 +
| 3.3V supply voltage
 +
| C1 bypass to 3.3V
 +
|
 +
|-
 +
| 55
 +
| P33/FAN1
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 57
 +
| KCLK
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 59
 +
| MCLK
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 60
 +
| VSS
 +
| Power
 +
| Ground
 +
| GND
 +
|
 +
|-
 +
| 61
 +
| IRRX2/GP34
 +
|
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 65
 +
| VCC
 +
| Power
 +
| 3.3V supply voltage
 +
| C9 bypass to 3.3V
 +
|
 +
|-
 +
| 76
 +
| VSS
 +
| Power
 +
| Ground
 +
| GND (C10)
 +
|
 +
|-
 +
| 84
 +
| RXD1
 +
| Input
 +
|
 +
| U3 8
 +
U2 18
 +
|
 +
|-
 +
| 85
 +
| TXD1
 +
| Output
 +
|
 +
| U3 6
 +
U2 17
 +
|
 +
|-
 +
| 86
 +
| nDSR1
 +
| Input
 +
| Data set ready
 +
| U3 ?
 +
| Optional flow control
 +
|-
 +
| 87
 +
| nRTS1
 +
| Output
 +
| Request to send
 +
| U3 ?
 +
| Optional flow control
 +
|-
 +
| 93
 +
| VCC
 +
| Power
 +
|
 +
| C21 bypass to 3.3V
 +
|
 +
|-
 +
| 95
 +
| RXD2
 +
| Input
 +
|
 +
| Trace open?
 +
|
 +
|-
 +
| 96
 +
| TXD2
 +
| Output
 +
|
 +
| Trace hidden under IC?
 +
|
 +
|-
 +
| 97
 +
| nDSR2
 +
| Input
 +
| Data set ready
 +
| Trace open?
 +
| Optional flow control
 +
|-
 +
| 98
 +
| nRTS2
 +
| Output
 +
| Request to send
 +
| Trace hidden under IC?
 +
| Optional flow control
 +
|-
 +
| 101
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|-
 +
| 102
 +
| HVCC
 +
| Power
 +
|
 +
| C24 bypass to 3.3V
 +
|
 +
|-
 +
| 103
 +
| SDA
 +
| I/O
 +
|
 +
| J9 14
 +
|
 +
|-
 +
| 104
 +
| SCLK
 +
| I/O
 +
|
 +
| J9 13
 +
|
 +
|-
 +
| 105
 +
| A0/RESET#
 +
|
 +
|
 +
| R10 (10k) pull-up to 3.3V
 +
|
 +
|-
 +
| 111
 +
| HVCC
 +
| Power
 +
|
 +
| C32 bypass to 3.3V
 +
|
 +
|-
 +
| 112
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|-
 +
| 121
 +
| HVCC
 +
| Power
 +
|
 +
| C33 bypass to 3.3V
 +
|
 +
|-
 +
| 122
 +
| HVCC
 +
| Power
 +
|
 +
| C34 bypass to 3.3V
 +
|
 +
|-
 +
| 125
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|-
 +
| 126
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|-
 +
| 127
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|-
 +
| 128
 +
| HVSS
 +
| Power
 +
|
 +
| GND
 +
|
 +
|}
 +
 
 +
=== J9 LPC header===
 +
 
 +
NOTE: version 1.3+ motherboards are missing the LFRAME signal which will need to be generated by an external CPLD [https://www.reddit.com/r/originalxbox/comments/7uo3lq/got_an_xbox_for_free_dvd_tray_wont_stop_ejecting/dtmqmn3/]
 +
 
 +
NOTE: version 1.5 motherboards are missing pins 2 (GND) and 9 (VCC3), and pins 12 (GND) and 15 (VCC3) haven't been confirmed to work correctly{{citation needed}}
 +
 
 +
{| class="wikitable"
 +
!| Pin
 +
! Name
 +
! Type
 +
! Description
 +
! Termination(s)
 +
! Notes
 +
|-
 +
| 1
 +
| LCLK
 +
| Output
 +
| PCI clock
 +
| U1 29
 +
|
 +
|-
 +
| 2
 +
| VSS
 +
| Power
 +
| System ground
 +
| (see other parts)
 +
|
 +
|-
 +
| 3
 +
| LFRAME#
 +
| Output
 +
| Frame signal
 +
| U1 24
 +
| Indicates start of a new cycle and termination of broken cycle.
 +
|-
 +
| 4
 +
| ---
 +
| ---
 +
| ---
 +
| ---
 +
| Voided to ensure correct ribbon cable alignment.
 +
|-
 +
| 5
 +
| LRST#
 +
| Output
 +
| PCI reset
 +
| U1 26
 +
| Used as LPC interface reset.
 +
|-
 +
| 6
 +
| VCC5
 +
| Power
 +
| 5V power supply
 +
| (see other parts)
 +
| C12(e), C13(S), C15(S), U3 11
 +
|-
 +
| 7
 +
| LAD3
 +
| I/O
 +
| LPC address/data bus
 +
| U1 23
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 8
 +
| LAD2
 +
| I/O
 +
| LPC address/data bus
 +
| U1 22
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 9
 +
| VCC3
 +
| Power
 +
| 3.3V power supply
 +
| (see other parts)
 +
|
 +
|-
 +
| 10
 +
| LAD1
 +
| I/O
 +
| LPC address/data bus
 +
| U1 21
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 11
 +
| LAD0
 +
| I/O
 +
| LPC address/data bus
 +
| U1 20
 +
| Multiplexed command, address and data bus.
 +
|-
 +
| 12
 +
| VSS
 +
| Power
 +
| System ground
 +
| (see other parts)
 +
|
 +
|-
 +
| 13
 +
| SCL
 +
| I/O
 +
| SMBus clock signal
 +
| U1 104
 +
|
 +
|-
 +
| 14
 +
| SDA
 +
| I/O
 +
| SMBus data signal
 +
| U1 103
 +
|
 +
|-
 +
| 15
 +
| VCC3
 +
| Power
 +
| 3.3V power supply
 +
| (see other parts)
 +
| Intended to be used for external IO board
 +
|-
 +
| 16
 +
| L_SER_IRQ
 +
| Input
 +
| Serial interrupt requests
 +
| U1 30
 +
| Provides a serial interrupt request line for mouse/keyboard implementations of the IO board.
 +
|}
  
 
== Related links ==
 
== Related links ==
Line 18: Line 815:
 
* [https://github.com/espes/xqemu/blob/xbox/hw/xbox/lpc47m157.c Super I/O emulation in XQEMU]
 
* [https://github.com/espes/xqemu/blob/xbox/hw/xbox/lpc47m157.c Super I/O emulation in XQEMU]
 
(SMBus?)
 
(SMBus?)
 +
* [https://imgur.com/a/ROMYa Images (CC0 License) by Codeasm with detailed shots of the SuperIO board]

Latest revision as of 22:25, 26 June 2021

The Super I/O board is a feature of some Development Kits. The board is build around a SMSC LPC47M157 chip (Datasheet) and interfaces with the Xbox via a ribbon cable connected to the LPC Debug Port.

Super I/O board from a DVT4

The board provides the following ports:

unpopulated ports or functions are:

Schematic

Its a four layer board, layers 2 and 3 are filled on the entire board, probably ground and power planes. north, or up in the next tables is up as written the layer numbers and silkscreen common direction. The folowing main parts are populated on the board:

total Labels Description
1 U1 SMSC LPC47M157-NC (1996 )
0 U2 unpopulated DIP24 MCU(?)
1 U3 MAX223EAI (0104, first week 2004?)
1 Y2 CMX-309FB B (14.3181Mhz standard Clock Oscillator )
1 J7 AMP rs232 Male connector
1 J9 16 pins male header (LPC bus)
5 R1,R7,R10,R11,R12 10Kohm smd resistor
7 C10,C12,C13,C16,C17,C36,C37 Bigger, probably NOT all the same caps
17 C1,C2,C9,C15,C1?(8?),C21,C22,C23,C24,C25,C26,C28,C31,C32,C33,C34,C35 Smaller, also, asuming not all the same

The connections in the following tables are checked with the continuity test on a VOM(Multimeter). but for now here are the listings of wich pin goes where:

U3 MAX223EAI [1]

Pin Name Type Description Termination(s) Notes
1 T3OUT
2 T1OUT
3 T2OUT
4 R2IN
5 R2OUT
6 T2IN
7 T1IN
8 R1OUT
9 R1IN
10 GND
11 VCC Power 5V supply voltage J9 6
12 C1+
13 V+
14 C1-
15 T4OUT
16 R3IN
17 R3OUT
18 SHDN
19 EN
20 R4IN
21 R4OUT
22 T4IN
23 T3IN
24 R5OUT
25 R5IN
26 V-
27 C2-
28 C2+

U1 SMsC LPC ic

Still lots to fill out here, but all connections required for kernel debugging via null-modem cable tied to TX/RX/GND have been accounted for.

Pin Name Type Description Termination(s) Notes
6 CLKI32 Input 32.768kHz trickle clock input GND (C17) Disabled via GND
7 VSS Power Ground GND (C17)
18 VTR Power 3.3V standby voltage C17 bypass to 3.3V Connected to VCC because no wakeup functionality is required
19 CLOCKI Input 14.318MHz clock input Y2 3
20 LAD0 I/O LPC address/data bus J9 11 Multiplexed command, address and data bus.
21 LAD1 I/O LPC address/data bus J9 10 Multiplexed command, address and data bus.
22 LAD2 I/O LPC address/data bus J9 8 Multiplexed command, address and data bus.
23 LAD3 I/O LPC address/data bus J9 7 Multiplexed command, address and data bus.
24 LFRAME# Input Frame signal J9 3 Indicates start of a new cycle and termination of broken cycle.
26 PCI_RESET# Input PCI reset J9 5 Used as LPC interface reset.
27 LPCPD# Input Power down signal R7 (10k) pull-up to 3.3V Indicates that it should prepare for power to be shut down on the LPC interface. Tied high relying on PCI_RESET to do its job.
29 PCI_CLK Input PCI clock J9 1
30 SER_IRQ Output Serial interrupt requests J9 16 Provides a serial interrupt request line for mouse/keyboard implementations of the IO board.
31 VSS Power Ground GND
32 GP10/J1B1 Trace open?
33 GP11/J1B2 Trace open?
34 GP12/J2B1 Trace open?
37 GP15/J1Y Trace open?
38 GP16/J2X Trace open?
39 GP17/J2Y Trace open?
40 AVSS Power Analog ground GND
42 GP21/P16/nDS1 Trace open?
44 VREF Power 3.3V reference voltage C2 bypass to 3.3V 5V or 3.3V used for the game port logic
45 GP24/SYSOPT R1 (10k) pull-down to GND Set the configuration base I/O address of 0x2E (R2 would be a pullup to 3.3V with a different configuration address)
47 GP26/MIDI_OUT Trace open?
49 GP61/LED2 Trace open?
51 GP30/FAN_TACH2 Trace open?
53 VCC Power 3.3V supply voltage C1 bypass to 3.3V
55 P33/FAN1 Trace open?
57 KCLK Trace open?
59 MCLK Trace open?
60 VSS Power Ground GND
61 IRRX2/GP34 Trace open?
65 VCC Power 3.3V supply voltage C9 bypass to 3.3V
76 VSS Power Ground GND (C10)
84 RXD1 Input U3 8

U2 18

85 TXD1 Output U3 6

U2 17

86 nDSR1 Input Data set ready U3 ? Optional flow control
87 nRTS1 Output Request to send U3 ? Optional flow control
93 VCC Power C21 bypass to 3.3V
95 RXD2 Input Trace open?
96 TXD2 Output Trace hidden under IC?
97 nDSR2 Input Data set ready Trace open? Optional flow control
98 nRTS2 Output Request to send Trace hidden under IC? Optional flow control
101 HVSS Power GND
102 HVCC Power C24 bypass to 3.3V
103 SDA I/O J9 14
104 SCLK I/O J9 13
105 A0/RESET# R10 (10k) pull-up to 3.3V
111 HVCC Power C32 bypass to 3.3V
112 HVSS Power GND
121 HVCC Power C33 bypass to 3.3V
122 HVCC Power C34 bypass to 3.3V
125 HVSS Power GND
126 HVSS Power GND
127 HVSS Power GND
128 HVSS Power GND

J9 LPC header

NOTE: version 1.3+ motherboards are missing the LFRAME signal which will need to be generated by an external CPLD [2]

NOTE: version 1.5 motherboards are missing pins 2 (GND) and 9 (VCC3), and pins 12 (GND) and 15 (VCC3) haven't been confirmed to work correctly[citation needed]

Pin Name Type Description Termination(s) Notes
1 LCLK Output PCI clock U1 29
2 VSS Power System ground (see other parts)
3 LFRAME# Output Frame signal U1 24 Indicates start of a new cycle and termination of broken cycle.
4 --- --- --- --- Voided to ensure correct ribbon cable alignment.
5 LRST# Output PCI reset U1 26 Used as LPC interface reset.
6 VCC5 Power 5V power supply (see other parts) C12(e), C13(S), C15(S), U3 11
7 LAD3 I/O LPC address/data bus U1 23 Multiplexed command, address and data bus.
8 LAD2 I/O LPC address/data bus U1 22 Multiplexed command, address and data bus.
9 VCC3 Power 3.3V power supply (see other parts)
10 LAD1 I/O LPC address/data bus U1 21 Multiplexed command, address and data bus.
11 LAD0 I/O LPC address/data bus U1 20 Multiplexed command, address and data bus.
12 VSS Power System ground (see other parts)
13 SCL I/O SMBus clock signal U1 104
14 SDA I/O SMBus data signal U1 103
15 VCC3 Power 3.3V power supply (see other parts) Intended to be used for external IO board
16 L_SER_IRQ Input Serial interrupt requests U1 30 Provides a serial interrupt request line for mouse/keyboard implementations of the IO board.

Related links

(SMBus?)

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