3202

ND 120 CPU board, component side.

ND 120 CPU board, solder side.

3202 is the ND-120 CPU board.

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Introduction

It contains the CPU, bus arbitration logic, memory control, memory and other subsystems. It also has the Real time clock and the I/O for the serial console.

Switches and indicators

• SW3 - Master Clear - normal position = central. This switch may be depressed to give a hardware master clear to the CPU.
• TH1 - ALD select
• TH2 - Baud rate select
• LED3 - self test passed (green)
• LED2 - self test fail (red)
• LED1 - cache OFF (red)
• SW1 - Cache ON, normal position = down.
• LED6 - CPU grant (green)
• LED7 - bus grant (yellow)
• SW2 - Memory OFF, normal position = down.
• LED4 - parity error (red)
• LED5 - parity disable (red)
• SW4 - Parity disable, normal position = down.
• upper limit display
  • 000 - memory off (SW2)
  • 100 - 2M Bytes onboard memory
  • 200 - 4M Bytes onboard memory
  • 300 - 6M Bytes onboard memory

Connectors

The A and B connectors are used for I/O, the C connector is used for the ND-100 Bus.

I/O Devices on the card

none?

ECO

ECO or Engineering Change Order is a hardware change. Here is a list of known ECO's for this card.

• ECO 100-774 - Memory out of range
• ECO 100-779 - System failing with cache enabled
• ECO 100-785 - Memory out of range, IOX-error
• ECO 100-786 - Upgrade ND-120CX CPU & MM 32B 2MB to ND-125CX
• ECO X01 - New backup battery for the calendar on ND-120 CPU

Reference

• Norsk Data Document ND–30.008.3 EN ND-100 Hardware Maintenance , page 255