SUPER MICRO Computer IRV-3702 Interrupt Controller, Timers, CLOCK/CALENDAR and Cmos RAM

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INTERRUPT CONTROLLER

The IRV-3702 SBC has the equivalence of two 82C59A interrupt controllers included in the System Controller chip. The controllers accept requests from peripherals, resolve priorities on pending interrupts and interrupts in service, interrupt the CPU, and provide the vector address of the interrupt service routine. The two interrupt controllers are cascaded in a fashion compatible with the IBM PC/AT. The interrupt priority and assignments are shown below in descending order of priority:

Highest

IOCHCK/

Parity Check (Non-maskable)

 

IRQ0

System Timer (Not Available)

 

IRQ1

Keyboard (Not Available)

 

IRQ8

Real Time Clock (Not Available)

 

IRQ9

VGA Controller

 

IRQ10

Not Used

 

IRQ11

Not Used

 

IRQ12

Not Used

 

IRQ13

Co-processor (Not Available)

 

IRQ14

EIDE Disk Controller

 

IRQ15

Not Used

 

IRQ3

Serial Port 2

 

IRQ4

Serial Port 1

 

IRQ5

Alternate for Parallel Port

 

IRQ6

Floppy Disk Controller

Lowest

IRQ7

Parallel Port

The interrupt request lines IRQx and IOCHCK/ are available on the 98-pin edge connector except as noted above.

TIMERS

The IRV-3702 SBC has the equivalence of an 82C54 Programmable Timer included in the System Controller chip. The 82C54 is a three channel Programmable Counter/Timer chip. The three timers are driven by a 1.19MHz clock source derived from the on-board 14.31818MHz crystal oscillator. The three timers are used as follows:

TIMER Channel 0: System Timer

TIMER Channel 1: Timer for DRAM refresh

TIMER Channel 2: Tone Generation for Audio

CLOCK/CALENDAR AND CMOS RAM

The IRV-3702 SBC includes a DS12B887 real time clock/calendar with 128 bytes of CMOS RAM and integral Lithium battery which provides over 10 years of data retention when the system power is off.

The 128 byte CMOS RAM consists of 14 bytes used by the clock/calendar, and 114 bytes used by the system BIOS.

KEYBOARD PORT

The IRV-3702 SBC contains an IBM PC/AT compatible keyboard controller for interfacing to a generic IBM PC/AT compatible keyboard. The keyboard controller assembles the serial data from the keyboard into bytes and interrupts the CPU via IRQ1 after each byte is ready to be read. The IRQ1 service routine reads port 60H to get the keyboard scan code and acknowledges by sending a positive

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Contents Micro Computer SPECIALISTS, INC Page Preface Page Table of Contents Page Introduction FeaturesProcessor System DescriptionSystem Memory Sdram DMA ControllerInterrupt Controller TimersCLOCK/CALENDAR and Cmos RAM Keyboard PortMouse Port Reset SwitchSpeaker Port Printer PortEide Hard Disk Port Watchdog TimerOptional PROMDISK-CHIP Disk Emulator High Speed PCI Expansion BUSIrda Infrared Interface Port Ethernet Port Universal Serial BUS PortSetup Using the PROMDISK-CHIP Disk Emulator Using ROM-DOSAND Other Disk Operating SystemsPromdisk LOW Level Format Installing the Dimms InstallationInstalling the CPU Installing the PROMDISK-CHIPCompleting the Installation CPU Appendix a SpecificationsAppendix B Board Outline IRV-3702 SBC Memory Map Address Used For Size Appendix C Memory and I/O MapsIRV-3702 SBC I/O Map Address FunctionCN8 Keyboard Header/Connector Appendix D ConnectorsCN18 Keyboard/Mouse Connector PS2 type CN7 Keylock Header/ConnectorCN4 Printer Interface Connector CN1 & CN3 IDE Hard Disk Port ConnectorsCN5 Ethernet LED Connector CN10 Ethernet RJ45 ConnectorCN11 Serial Port #2 10-pin Header/Connector CN12 Serial Port #1 9-pin Sub D ConnectorJ1 VGA Display Connector 15-pin Sub-D CN7 Speaker Port Header/ConnectorCN17 PS2 Mouse Header/Connector CN7 IDE LED Header/ConnectorCN9 Universal Serial Bus Ports 1 & 2 Connector CN6 IrDA Infrared Port ConnectorJP15 Appendix E Configuration JumpersMultiplier TimeJP4 Clear Cmos Setup Jumper Appendix F Bios Error Beep Codes