MV20556

MOSEL VITELIC INC.

6/27

PID256** 07/97

Specifications subject to change without notice, contact your sales representatives for the most recent information.

Preliminary

Memory Map Details

Internal RAM

The MV20556 contains a 128-byte Internal Data RAM

(Which includes registers R7-R0 in each of four Banks),

and

twenty

memory-mapped

Special

Function

Registers.

Internal Data RAM

The Internal Data RAM provides a convenient 128-byte

scratch pad memory.

Register Banks

There are four Register Banks within the Internal Data

RAM. Each Register Bank contains registers R7-R0.

128 Addressable Bits

There are 128 addressable software flags in the

Internal Data RAM. They are located in the 16 byte

locations starting at byte address 32 and ending with

byte location 47 of the RAM address space.

Stack

The stack may be located anywhere within the Internal

Data RAM address space. The stack may be as large

as 128 bytes on the MV20556.

7Fh

30h

2Fh

20h

1Fh

18h

17h

10h

0Fh

08h

07h

00h

RS1 RS0

11

10

01

00

Four

bank

area

bit

addressable

area

scratch

pad

area

R7

R0

R7

R0

R7

R0

R7

R0

128B RAM Bit Address

128B RAM Memory Map

Bank 3

Bank 2

Bank 1

Bank 0

(MSB)

(LSB)

RAM

BYTE

127

7FH

2FH

2EH

2DH

2CH

2BH

2AH

29H

28H

27H

26H

25H

24H

23H

22H

21H

20H

1FH

18H

17H

00H

10H

0FH

08H

07H

47

46

45

44

43

42

41

40

39

38

37

36

35

34

33

23

24

0

16

15

8

7

32

31

78

70

68

60

58

50

48

40

38

30

28

20

18

10

08

00

79

71

69

61

59

51

49

41

39

31

29

21

19

11

09

01

7A

72

6A

62

5A

52

4A

42

3A

32

2A

22

1A

12

0A

02

7B

73

6B

63

5B

53

4B

43

3B

33

2B

23

1B

13

0B

03

7C

74

6C

64

5C

54

4C

44

3C

34

2C

24

1C

14

0C

04

7D

75

6D

65

5D

55

4D

45

3D

35

2D

25

1D

15

0D

05

7E

76

6E

66

5E

56

4E

46

3E

36

2E

26

1E

16

0E

06

7F

77

6F

67

5F

57

4F

47

3F

37

2F

27

1F

17

0F

07