MVME5100 Single Board Computer Programmer's Reference Guide

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Caution
Programming Model
sien When sien is set, the logging of a single-bit error causes
the int bit to be set if it is not already. When the int bit is
set, the Hawk’s internal error interrupt is asserted.
mien When mien is set, the logging of a non-correctable error
causes the int bit to be set if it is not already. When the int
bit is set, the Hawk’s internal error interrupt is asserted.
int int is set when one of the SMC’s interrupt conditions
occurs. It is cleared by reset or by software writing a one
to it. The Hawk’s internal error interrupt tracks int. When
int is set, Hawk’s internal error interrupt is asserted. When
int is cleared, Hawk’s internal error interrupt is negated.
mbe_me When mbe_me is set, the detection of a multiple-bit error
during a PowerPC read or write to SDRAM causes the
SMC to pulse its machine check interrupt request pin
(MCHK0_) true. When mbe_me is cleared, the SMC
does not assert its MCHK0_ pin on multiple-bit errors.
The SMC never asserts its MCHK0_ pin in response to a
multiple-bit error detected during a scrub cycle.
The Hawk’s internal error interrupt and the MCHK0_ pin are the only nonpolled
notification that a multiple-bit error has occurred. The SMC does
not assert TEA as a result of a multiple bit error. In fact, the SMC does not
have a TEA_ signal pin and it assumes that the system does not implement
TEA.
http://www.motorola.com/computer/literature 3-49
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