Programming Model

 

 

Note This register is configured only during power-up-reset and is

 

 

 

unchanged by software or local reset.

 

 

 

ADR/SIZ

 

 

1st $FFF4301C/2nd $FFF4311C (8-bits)

 

 

BIT

31

30

29

28

27

26

25

24

4

NAME

BCK7

BCK6

BCK5

BCK4

BCK3

BCK2

BCK1

BCK0

 

OPER

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

 

RESET

0 P

0 P

0 P

1 P

1 P

0 P

0 P

1P

 

Data Control Register

ADR/SIZ

 

 

1st $FFF43020/2nd $FFF43120 (16-bits)

 

 

 

 

 

 

 

 

 

 

 

BIT

31

30

 

29

28

27

26

25

24

 

 

 

 

 

 

 

 

 

 

NAME

0

0

 

DERC

ZFILL

RWCKB

0

0

0

 

 

 

 

 

 

 

 

 

 

OPER

R

R

 

R/W

R/W

R/W

R

R

R

 

 

 

 

 

 

 

 

 

 

RESET

X

X

 

1 PLS

0 PLS

0 PLS

X

X

X

 

 

 

 

 

 

 

 

 

 

RWCKB READ/WRITE CHECKBITS, when set, enables the data from the seven checkbits in the Petra MCECC sector (bits 30-24) to be written and read on the local MC680x0 data bus. This bit should be cleared for normal system operation.

Note that if test software forces a single-bit error to a location (line) using this function, the scrubber may correct the location before the test software gets a chance to check for the single-bit error at that location. This can be avoided by disabling scrubbing and making sure that all previous scrubs have completed before performing the test. Also note that writing bad checkbits can set the ERRLOG bit in the Error Logger register.

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

4-17

Page 265
Image 265
Motorola MVME1X7P manual Data Control Register, Unchanged by software or local reset