Intel Atom N2800 User Manual

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5.5 Port 80h POST Codes
During the POST, the BIOS generates diagnostic progress codes (POST codes) to I/O
port 80h. If the POST fails, execution stops and the last POST code generated is left at
port 80h. This code is useful for determining the point where an error occurred.
Displaying the POST codes requires a POST card that can interface with the Debug
header. The POST card can decode the port and display the contents on a medium
such as a seven-segment display. Refer to the location of the Debug header in
Figure 1.
The following tables provide information about the POST codes generated by the BIOS:
 Table 50 lists the Port 80h POST code ranges
 Table 51 lists the Port 80h POST codes themselves
 Table 52 lists the Port 80h POST sequence

NOTE
In the tables listed above, all POST codes and range values are listed in hexadecimal.
Table 50. Port 80h POST Code Ranges
Range
Subsystem
0x00  0x05
Entering SX states S0 to S5.
0x10, 0x20, 0x30
Resuming from SX states (0x10 0x20  S2, 0x30  S3, etc.)
0x11  0x1F
PEI phase pre MRC execution
0x21  0x29
MRC memory detection
0x2A  0x2F
PEI phase post MRC execution
0x31  0x35
Recovery
0x36  0x3F
Platform DXE driver
0x41  0x4F
CPU Initialization (PEI, DXE, SMM)
0x50  0x5F
I/O Buses: PCI, USB, ATA etc. 0x5F is an unrecoverable error. Start with PCI.
0x60  0x6F
BDS
0x70  0x7F
Output devices: All output consoles.
0x80  0x8F
For future use
0x90  0x9F
Input devices: Keyboard/Mouse.
0xA0  0xAF
For future use
0xB0  0xBF
Boot Devices: Includes fixed media and removable media. Not that critical since
consoles should be up at this point.
0xC0  0xCF
For future use
0xD0  0xDF
For future use

Intel Atom N2800 Specifications

General

Processor Number	N2800
Number of Cores	2
Number of Threads	4
Base Frequency	1.86 GHz
TDP	6.5 W
Instruction Set	64-bit
Lithography	32 nm
Launch Date	Q1'12
Instruction Set Extensions	SSE2, SSE3, SSSE3
Embedded Options Available	Yes
Max Memory Size	4 GB
Number of Memory Channels	1
Processor Graphics	Intel® Graphics Media Accelerator 3650
Graphics Base Frequency	640 MHz
Graphics Max Dynamic Frequency	640 MHz
Sockets Supported	BGA559
Max CPU Configuration	1
Idle States	Yes
Intel® 64	Yes
Intel® Identity Protection Technology	No
PCI Express Revision	2.0
Cache	1 MB
Memory Types	DDR3 800
PCI Express Configurations	1x4