IBM PC 300PL manual Hard disk drives and controller, Software compatibility, Software interrupts

Page 32

Chapter 6. System compatibility

4.Waits one I/O delay

5.Enables the interrupt through the Set Interrupt Enable Flag command

Hardware interrupt IRQ9 is defined

as the

replacement interrupt

level

for the cascad

Program interrupt sharing is implemented

on IRQ2, interrupt hex 0A.

The

following processing

maintain compatibility with the IRQ2

used by

IBM Personal Computer

products:

1. A device drives the interrupt request active on IRQ2 of the channel.

2. This interrupt request is mapped in hardware to IRQ9 input on the second interrupt

3.When the interrupt occurs, the system microprocessor passes control to the IRQ9 ( interrupt handler.

4. This interrupt

handler performs

an EOI command to the second interrupt controller and

to the IRQ2

(interrupt hex 0A)

interrupt handler.

5. This IRQ2 interrupt handler, when handling the interrupt, causes the device to rese request before performing an EOI command to the master interrupt controller that fini the IRQ2 request.

Hard disk drives and controller

Reading from and writing to the hard disk is initiated in the same way as in IBM Pe products; however, new functions are supported.

Software compatibility

To maintain software compatibility, the interrupt polling mechanism that is used by IBM P products is retained. Software that interfaces with the reset port for the IBM Pers positive-edge interrupt sharing (hex oraddress06Fx, where02Fx is the interrupt level) does not creat interference.

Software interrupts

With the

advent

of

software interrupt sharing, software interrupt routines must daisy

routine must check the function value, and

if

it is

not in

the range of function calls

transfer

control

to

the next routine in the chain. Because

software

interrupts

are ini

address

0:0

before

daisy chaining,

check

for

this

case.

If

the

next routine

is

poin

the

function

call

is

out of range,

the appropriate

action

is

to

set

the carry

flag

an

error

condition.

 

 

 

 

 

 

 

 

 

 

 

Machine-sensitive programs

Programs

can select machine-specific features, but

they must first identify the

machine

IBM

has

defined methods for uniquely determining

the specific machine type. The machin

can

be

found through Interrupt 15H, Return System

Configuration Parameters function

(AH)=C0

24 Technical Information Manual

Image 32
Contents Page 1999 ApplyAre WithContents Bios Error codesSystem software PostReferences Index Contents Recovery jumper Power-input requirements USB port Internal DasdPreface Related publicationsTerminology usage ViiExpressing storage Capacity Equals EqualsBytes, and2 073 824 System overview Major featuresSystem overview Other features POST/BIOSNetwork support PCIOn Ring Features System board featuresFeatures SystemSystem memory RimmUSB interface PCI busIDE bus master interface Video subsystem BusInterface Plug Play support Advanced Power List Bus Mastering Support For Fast Performance 64-bit 125Video subsystem resources Resource AssignmentAudio subsystem FeaturesMonitor support Super input/output controller Diskette Drive interfaceSeria l ports PortRPL Keyboard and mouse portsNetwork connection System board features Real-time Flash EepromExpansion adapters Physical layoutSystem board, Types 6584 Riser card layoutsRecovery jumper Cable connectorsRecovery jumper DVIConnector panel System boardPhysical specifications This Section Lists Physical Specifications ForTypes 6584 and 6594. NICTower Requirements ForWake LAN adapters Have Pin Right-angle Header For AUX5Power supply Power inputPower output Power supplyComponent outputs Components draw less current than Maximum ShownConnector description Output protectionSystem software System softwarePlay Flash update utility program Diagnostic programConfiguration/Setup UtilitySystem compatibility Hardware compatibilityHardware interrupts System compatibilityHard disk drives and controller Software compatibilitySoftware interrupts Machine-sensitive programsAppendix A. Connector pin assignments Monitor connectorAppendix A. Connector pin assignments Monitor port connector pin assignments-SVGAMemory connectors System memory connector pin assignmentsPin Signal Pin assignmentsPCI connector pin assignments Pin AssignmentsConnector PinConnector slot One Only For All Other slots, the signal Connectors Are on Riser cardThese Assignments Are For For pin A41IDE connectors IDE connector pin assignmentsConnector Diskette drive connector pin assignmentsPower supply connector pin assignments Pin Signal nameAlert on LAN connectors Tamper detection switchConnector pin Radio frequency identification Rfid pin assignmentsCD audio connector USB port connectorsPort KeyboardKeyboard port connector pin assignments Serial port connector pin assignmentsParallel port connector pin assignments ConnectorPin Signal Ground Appendix B. System address maps SystemInput/output AppendixMaps O address mapAre Reserved DMA I/O address mapHex Size Description Bits Byte PointerSystem address maps ConfigurationMap Appendix C. IRQ and DMA channel assignments Appendix C. IRQ and DMA channel assignmentsIRQ channel assignments DMA channel assignmentsAppendix D. Error codes Appendix D. Error CodesCodes Beep codesReference Appendix E. Notices and trademarksReferences This Publication References Advanced PowerSpecification Index ConnectorIndex Features Wake on LAN 2 Wake on Ring MemoryRfid