Ampro Corporation Littleboard 550 manual Watchdog Timer, Hot Cable Jumper

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Chapter 3

Hardware

for the serial port 1. As an alternate, you can short the equivalent pins (pins 7 and 9) on the respective DB9 port connector as shown in Figure 3-3.

Serial A Interface (J11)

19

9 7 5 3 1

1

2

3

4

5

 

Or

Standard DB9 Serial

 

 

 

 

for Serial Port 1

 

 

 

 

 

(or COM1 Port)

 

 

Port Connector (Female)

 

 

 

 

20

10 8 6 4 2

Rear View

 

 

 

 

Top View

6

7

8

9

 

 

 

 

 

Figure 3-3. Hot Cable Jumper

LB550Hotcable

Watchdog Timer

The watchdog timer (WDT) restarts the system if a mishap occurs, ensuring proper start-up after the interruption. Possible problems include failure to boot properly, the application software’s loss of control, failure of an interface device, unexpected conditions on the bus, or other hardware or software malfunctions.

The WDT (watchdog timer) can be used both during the boot process and during normal system operation.

During the Boot process – If the operating system fails to boot in the time interval set in the BIOS, the system will reset.

Enable the WDT in the Advanced BIOS Features of BIOS Setup. Set the WDT for a time-out interval in seconds, between 2 and 255, in one second increments in the Advanced BIOS Features screen. Ensure you allow enough time for the boot process to complete and for the OS to boot. The OS or application must tickle (turnoff) the WDT as soon as it comes up. This can be done by accessing the hardware directly or through a BIOS call.

During System Operation – An application can set up the WDT hardware through a BIOS call, or by accessing the hardware directly. Some Ampro Board Support Packages provide an API interface to the WDT. The application must tickle (turnoff) the WDT in the time set when the WDT is initialized or the system will be reset. You can use a BIOS call to tickle the WDT or access the hardware directly.

The BIOS implements interrupt 15 function 0C3h to manipulate the WDT.

Watchdog Code examples – Ampro has provided source code examples on the LittleBoard 550 Doc & SW CD-ROM illustrating how to control the WDT. The code examples can be easily copied to your development environment to compile and test the examples, or make any desired changes before compiling. Refer to the WDT Readme file in the Miscellaneous Source Code Examples subdirectory, under the LittleBoard 550 Software menu on the LittleBoard 550 Doc & SW CD-ROM.

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Reference Manual

LittleBoard 550

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Contents LittleBoard Single Board Computer Reference Manual Audience Assumptions Contents Appendix a List of Tables Table A-1 Specifications Purpose of this ManualReference Material Related Ampro Products LittleBoard 550 Support ProductsOther LittleBoard Products Other Ampro Products Chapter Product Overview EBX ArchitectureProduct Description Stacking PC/104 Modules with the LittleBoardBoard Features Chapter Chapter Block Diagram ATAVIA Major Integrated Circuits ICsChip Type Mfg Model Description Function CPUAdditional Components Connector DefinitionsJack # Signal Description DIMM1Northb Indicator Definition Jumper # Installed Removed/InstalledDefault Jumper DefinitionsThb Specifications Physical SpecificationsDimension Mechanical Specifications LittleBoard 550 Dimensions Top view, #1115 705 415 730 200 050 350 800 600 385 345 Power Specifications Environmental SpecificationsThermal/Cooling Requirements Reference Manual LittleBoard Overview USBSdram Memory DIMM1 CPU U1Memory Flash Memory U17Interrupt Channel Assignments Memory MapAddress hex Subsystem Address MapBase Address Function VGAPin # Signal Input Description Output PC/104-Plus Interface J21GNT1 IDSEL0REQ0 CLK2Intd REQ2CLK0 IntaGNT2 IDSEL1REQ1 CLK3GNT0 IDSEL2IDSEL3 CLK1Pin # Signal Description J1 Row a PC/104 Interface J1A,B,C,DPin # Signal Descriptions J1 Row B DACK1 DACK3DRQ3 DRQ1Pin # Signal Descriptions J1 Row C Pin # Signal Descriptions J1 Row DDACK0 IRQ15IRQ14 DRQ0Pin # Signal Description IDE Interface J12, J17Pdior PdreqPdiow PdiordySDD9 SDD8SDD6 SDD5SDA2 SDA1SDA0 SDCS1#CompactFlash Adapter J23 PDCE1VCC PDCE2 PdrstFloppy Drive Interface J14 Pin # Signal In/Out Description Parallel Port Interface J15Serial Interfaces J11, J13 RS485 Serial Port ImplementationRXD1 DCD1DSR1 RTS1DCD3 CTS2DTR2 DSR3RXD4 DCD4DSR4 RTS4Utility Interfaces Utility 1 Interface J16Utility 2 Interface J24 Mouse InterfaceSystem Management Bus SMBus USB Signals USB0 and USB1 Component Address BinarySdram Eprom Batlow SuscPwrbt MdataUSB Signals USB2 and USB3 Utility 3 Interface J18Ethernet Interfaces J7, J32 TX+Audio Interface J28 Videor VideolVideognd CDLVideo Interfaces J3, J4, J5, J31 CRT InterfaceLCD Interface Enavdd Pin # Signal Description Line Channel Lvds InterfaceMiscellaneous Temperature MonitoringOops! Jumper Bios Recovery Real Time Clock RTCWatchdog Timer Hot Cable JumperCPU Fan Power Interface J10Power Monitor TAGReference Manual LittleBoard Accessing Bios Setup VGA Display IntroductionAccessing Bios Setup Serial Console Bios Setup Menu Item/TopicBios Menus Bios Setup Opening ScreenDate & Time Bios Configuration ScreenDrive Configurations and Boot Options Drive Assignment# of Floppy Drives Bios Settings Boot Order Drive and Boot OptionsKeyboard and Mouse Configuration User Interface OptionsUser Interface Memory Control Options MemoryPower Management and Advanced User Options Power ManagementAdvanced features On-Board Serial Ports On-Board LPT Port Video, Flat Panel, and Audio Options On-Board ControllersOn-Board Video PCI, Plug n Play, and Interrupt Assignments Chapter Bios Setup Chapter Bios Setup Chapter Bios Setup Splash Screen Customization Splash Screen Image RequirementsConverting the Splash Screen File \splashconvert convert.idf Appendix a Technical Support Method Contact InformationAppendix a Technical Support Connector Designation Pin # Mfg Part Number Appendix B Appendix C LAN Boot Option PXE Boot Agent Bios Setup Accessing PXE Boot Agent Bios SetupPXE Boot Agent Setup Screen PXE ConfigurationTCP/IP Configuration NetWare Configuration RPL ConfigurationCD-ROM CRTDocumentation and Support Software Doc & SW CD-ROM PostSupported features WDTReference Manual LittleBoard