EM78611

Universal Serial Bus Microcontroller Series

Preliminary

11

06/10/2003 (V1.0)

R4 (RAM Select Register)

Default Value: (0B_00XX_XXXX)

7

6

5

4

3

2

1

0

BK1

BK0

Ad5

Ad4

Ad3

Ad2

Ad1

Ad0

R4 (RAM select register) contains the address of the registers.

R4 [0~5] are used to select registers in 0x00h~0x3Fh. The address 0x00~0x1F is common

space. After 0x1Fh, SRAM are divided into four banks. Use Bank Select Register.

R4 [6,7]

to select the registers bank (refer to the table below).The following are two

examples:

(1) R4=0001100 and R4=1001100 point to the same register 0x0Ch. Since

0x0Ch is in the common space, Bit 6 and Bit 7 are meaningless.

(2) R4=0111100 points to the register 0x3C in Bank 2.

R4[7]Bk1

R4[6]Bk0

RAM Bank #

0

0

1

1

0

1

0

1

Bank 0

Bank 1

Bank 2

Bank 3

R5 (Port5 I/O register)

Default Value: (0B_0000_0000)

7

6

5

4

3

2

1

0

P57

P56

P55

P54

P53

P52

P51

P50

R6 (Port 6 I/O register)

Default Value: (0B_0000_0000)

7

6

5

4

3

2

1

0

P67

P66

P65

P64

P63

P62

P61

P60

R7 (Port7 I/O register)

Default Value: (0B_0000_0000)

7

6

5

4

3

2

1

0

P77

P76

D- / P75 / DATA

D+ / P74 / CLK

-

P72

P71

P70

R8 (Port 8 I/O register) Default Value: (0B_0000_0000)

7

6

5

4

3

2

1

0

P87

P86

P85

P84

P83

P82

P81

P80

R9 (Port 9 I/O register)

Default Value: (0B_0000_0000)

7

6

5

4

3

2

1

0

P97

P96

P95

P94

P93

P92

P91

P90