Lanc error status and interrupt control registers, Lanc error status register, Lanc error status register -34 – Motorola MVME1X7P User Manual

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LANC Error Status and Interrupt Control Registers

This section provides addresses and bit level descriptions of the LANC
interrupt control registers and status register.

LANC Error Status Register

SCLR

Writing a 1 to this bit clears bits 25 through 27 (LTO,
EXT, and PRTY). Reading this bit always yields 0.

LTO,EXT,PRTY

These bits indicate the status of the last Local Bus error
condition encountered by the LANC while performing
DMA accesses to the Local Bus.

A Local Bus error condition is flagged by the assertion of
TEA*.

When the LANC receives TEA*:

If the source of the error is local time-out,
then LTO is set and EXT and PRTY are
cleared.

If the source of the TEA* is due to an error in
going to the VMEbus, then EXT is set and the
other two status bits are cleared.

If the source of the error is DRAM parity
check error, then PRTY is set and the other
two status bits are cleared.

If the source of the error is none of the above
conditions, then all three bits are cleared.

Writing a 1 to bit 24 (SCLR) also clears all three bits.

ADR/SIZ

$FFF42028 (8 bits)

BIT

31

30

29

28

27

26

25

24

NAME

PRTY

EXT

LTO

SCLR

OPER

R

R

R

R

R

R

R

W/R-0

RESET

0

0

0

0

0 PL

0 PL

0 PL

0

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