Programming Model

Memory Configuration Register

ADR/SIZ

 

 

1st $FFF43008/2nd $FFF43108 (8-bits)

 

 

 

 

 

 

 

 

 

 

 

BIT

31

30

 

29

28

27

26

25

24

 

 

 

 

 

 

 

 

 

 

NAME

0

0

 

FSTRD

RB4

RB3

MSIZ2

MSIZ1

MSIZ0

 

 

 

 

 

 

 

 

 

 

OPER

R

R

 

R

R

R

R

R

R

 

 

 

 

 

 

 

 

 

 

RESET

X

X

 

X

X

X

X

X

X

 

 

 

 

 

 

 

 

 

 

MSIZ2-MSIZ0

MSIZ2-MSIZ0 together define the size of the total memory to be controlled by the MCECC pair. These bits reflect the RSIZ2-RSIZ0 bits in the Defaults Register 1.

MSIZ2

MSIZ1

MSIZ0

Memory Size

 

 

 

 

0

0

0

4MB using one 144-bit wide

 

 

 

block of 256Kx4 DRAMs

 

 

 

 

0

0

1

8MB using two 144-bit wide

 

 

 

block of 256Kx4 DRAMs

 

 

 

 

0

1

0

16MB using one 144-bit wide

 

 

 

block of 1Mx4 DRAMs

 

 

 

 

0

1

1

32MB using two 144-bit wide

 

 

 

blocks of 1Mx4 DRAMs

 

 

 

 

1

0

0

64MB using one 144-bit wide

 

 

 

block of 4Mx4 DRAMs

 

 

 

 

1

0

1

128MB using two 144-bit wide

 

 

 

blocks of 4Mx4 DRAMs

 

 

 

 

1

1

0

Reserved

 

 

 

 

1

1

1

Reserved

 

 

 

 

Difference from MEMC040: NONE except that they reflect input pins on the MEMC040; while they reflect register bits that are initialized by the reset serial bit stream on the MCECC.

5

http://www.mcg.mot.com/literature

5-15

Page 305
Image 305
Motorola MVME172 manual Memory Configuration Register, MSIZ2-MSIZ0