Motorola MVME1X7P manual Scrub Control Register, RWB0 RWB0 is a general-purpose read/write bit

Models: MVME1X7P

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cleared during normal system operation. DERC also allows the write portion of a read-modify-write to complete regardless of whether or not there was a multiple bit error during the read portion of the read-modify-write. DERC also affects scrub cycles.

Scrub Control Register

4

 

ADR/SIZ

 

 

1st $FFF43024/2nd $FFF43124 (8-bits)

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

31

30

 

29

28

27

26

 

25

24

 

 

 

 

 

 

 

 

 

 

 

NAME

0

0

 

0

SCRB

SCRBEN

0

 

SBEIEN

RWB0

 

 

 

 

 

 

 

 

 

 

 

OPER

R

R

 

R

R

R/W

R

 

R/W

R/W

 

 

 

 

 

 

 

 

 

 

 

RESET

0 PLS

0 PLS

 

0 PLS

0 PLS

0 PLS

X

 

0 PLS

0 PLS

 

 

 

 

 

 

 

 

 

 

 

RWB0 RWB0 is a general-purpose read/write bit.

SBEIEN Setting SBEIEN causes the logging of a single-bit error to create a true pulse on the INT signal pin.

SCRBEN This control bit enables the scrubber to operate. When SCRBEN is set, the MCECC sector immediately performs a scrub of the entire DRAM array. When the scrub is complete, if software has cleared SCRBEN, then scrubbing is not done again, until software sets the SCRBEN bit. If software has not cleared the SCRBEN bit, then when the amount of time indicated in the Scrub Period (SBPD) register expires, the MCECC sector scrubs the DRAM array again. It continues to perform scrubs of the entire DRAM array at the frequency indicated in the SBPD register. The scrubber does not start a new scrub once the SCRBEN bit is cleared. The time between scrubs is approximately two seconds times the value stored in the SBPD register. Note that a power-up, local, or software reset stops the scrubber.

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Page 267
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Motorola MVME1X7P manual Scrub Control Register, RWB0 RWB0 is a general-purpose read/write bit