NEC nd-20292 manual Chapter

ND-20292

CHAPTER 5

APRIL, 1990

Five types of resets are recognized:

Tl Occurs the first time the system is turned on.

T2 Occurs during subsequent power failures.

T3 occurs when the CPU recognizes a system error (abnormal reset).

T4 Occurs when the CPU reset button is depressed.

T5 Occurs when a first or second initialization is performed from a programming station.

2.System Program (ROM) Check (Memory Block 5B2):

Program (ROM) errors can be-retrieved from the

system programming mode for each of the five program sections. The system performs daily checksums for each of the program sections and increments a peg count (up to 255) if problems are found.

3.Interface Slot Check (Memory Block 5B3):

The number of hardware communication errors for each interface ETU (ESI, SLI, COI, TLI, ECR, MFR, CNF AND VMI) can be retrieved from system programming mode. Each card is checked at 32 millisecond intervals and up to 255 errors can be shown. Every time the busy switch on an

ETU is switched OFF, the corresponding error count is incremented by one.

4.Terminal Check (Memory Block 5B4):

The number of hardware communication errors for terminals connected to an ESI-E ( ) ETU can

be retrieved from the system programming mode.

Each terminal is checked at 32 millisecond intervals and each time a particular terminal is

disconnected, the corresponding error count is incremented by one to a maximum of 255 errors.

5.Port Information (Memory Block lE5):

The number of port data communication (PAW, PRW) errors for each port is stored (up to 99

errors) and can be retrieved from system programming mode.

NOTE:The error count stored in each Memory Block can be cleared.

550.2 Maintenance Function

1.Forced Initialization (Reset Memory Blocks 3D1, 3D2,3D3 and 3D4) - In case certain troubles occur in the system, normal system operation may be restored by resetting the system or a particular

interface ETU or Multiline Terminal from the system programming mode.

2.Software/Hardware Status Check

A.Interface ETU (Memory Block 5B5) -

Software/Hardware information of each slot is displayed.

B.Terminal (Memory Block 5B6) -

Software/Hardware information of each terminal is displayed.

3.Data Dump Read Only (Memory Block 5C2) - RAM and ROM data can be examined in increments of 1, 4,6 or 8 bytes at a time.

4.System Data Change History (Memory Block 5Cl) When the system program is altered, the last change made and the date and time at which it occurred is stored in system memory and can be retrieved from system programming mode.

5.Busy Out/Restore - In case trouble does occur in the system, the defective device(s) (interface card, MFR channel or terminal) can be disabled from the system programming mode.

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