Motorola MVME1X7P manual Chip Prescaler Counter, Scrub Time On/Time Off Register, STOFF2-STOFF0

Models: MVME1X7P

1 316
Download 316 pages 46.44 Kb
Page 269
Image 269

Programming Model

Chip Prescaler Counter

This register reflects the current value in the prescaler counter. The Prescaler counter is used with the BCLK Frequency register to produce a 1MHz clock signal for use by the refresher and by the scrubber. The register is readable and writable for test purposes. Programming of this register is not recommended.

ADR/SIZ

 

 

1st $FFF43030/2nd $FFF43130 (8-bits)

 

 

 

 

 

 

 

 

 

 

 

BIT

31

30

 

29

28

27

26

25

24

 

 

 

 

 

 

 

 

 

 

NAME

CPS7

CPS6

 

CPS57

CPS4

CPS3

CPS2

CPS1

CPS0

 

 

 

 

 

 

 

 

 

 

OPER

R/W

R/W

 

R/W

R/W

R/W

R/W

R/W

R/W

 

 

 

 

 

 

 

 

 

 

RESET

0 P

0 P

 

0 P

0 P

0 P

0 P

0 P

0 P

 

 

 

 

 

 

 

 

 

 

4

Scrub Time On/Time Off Register

ADR/SIZ

 

 

1st $FFF43034/2nd $FFF43134 (8-bits)

 

 

 

 

 

 

 

 

 

 

BIT

31

30

29

28

27

26

25

24

 

 

 

 

 

 

 

 

 

NAME

RWB7

0

STON2

STON1

STON0

STOFF2

STOFF1

STOFF0

 

 

 

 

 

 

 

 

 

OPER

R/W

R

R/W

R/W

R/W

R/W

R/W

R/W

 

 

 

 

 

 

 

 

 

RESET

0 PLS

0

0 PLS

0 PLS

0 PLS

0 PLS

0 PLS

0 PLS

 

 

 

 

 

 

 

 

 

STOFF2-STOFF0

STOFF2-STOFF0 control the amount of time that the scrubber refrains from requesting use of the DRAM each time it gives it up during a scrub. They control the off time as follows:

http://www.motorola.com/computer/literature

4-21

Page 269
Image 269
Motorola MVME1X7P manual Chip Prescaler Counter, Scrub Time On/Time Off Register, STOFF2-STOFF0