EMC EM78612 User Manual
Page 15
EM78612
Universal Serial Bus Microcontroller
Product Specification (V1.0) 03.22.2006
•••• 13
(This specification is subject to change without further notice)
R4 (RAM Select Register)
Default Value: (0B_0xxx_xxxx)
7
6
5
4
3
2
1
0
-
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 is grouped into two banks.
R4 [6]
are used to select register banks. To select a registers bank, refer to the
following examples and the table below
:
R4=01111100 points to the register 0x3C in Bank 1.
R4[6]Bk0
RAM Bank #
0
1
Bank 0
Bank 1
R5 (Data Line I/O Register)
Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
-
-
-
-
-
-
D- or DATA D+ or CLK
R5 [0]
USB D+ line register or PS/2 clock interface register.
R5 [1]
USB D- line register or PS/2 data interface register.
These two bits are BOTH writable and readable when the MCU is operating under PS/2
mode. But under USB Mode, these two bits cannot be accessed.
R5 [2~7] NON Used .The value is zero.
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 (Port 7 I/O Register)
Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
-
-
-
-
P73
P72
P71
P70
R8 (Port 6 Wake-up Pin Selection Register)
Default Value: (0B_1111_1111)
7
6
5
4
3
2
1
0
/Wu67
/wu66
/Wu65
/Wu64
/Wu63
/Wu62
/Wu61
/Wu60
R8 [0 ~ 7] Select which of the Port 6 pins are to be defined to wake-up the MCU from
sleep mode. When the state of the selected pins changes during sleep
mode, the MCU will wake-up and execute the next instruction automatically.
1: Disable the wake-up function