em78p468n ELAN Microelectronics Corp, em78p468n Datasheet - Page 15

• Manufacturer Part Number: em78p468n
• Description: 8-bit Microcontroller
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.6) 12.31.2007
(This specification is subject to change without further notice)
6.1.5 R4/RSR (RAM Select Register)
(Address: 04h)
Bits 7 ~ 6 (RBS1 ~ RBS0): determine which bank is activated among the four banks.
Bits 5 ~ 0 (RSR5 ~ RSR0): used to select up to 64 registers (Address: 00~3F) in
6.1.6 R5/Port 5 (Port 5 I/O Data and Page of Register Select
(Address: 05h)
Bits 7~4: Four bits I/O registers of Port 5
User can use the IOC50 register to define each bit either as input or output.
Bits 3~1: Not used
Bit 0 (IOCPAGE): change IOC5 ~ IOCF to another page
6.1.7 R6/Port 6 (Port 6 I/O Data Register)
(Address: 06h)
Bits 7~0: 8-bit I/O registers of Port 6
User can use the IOC60 register to define each bit either as input or output.
6.1.8 R7/Port 7 (Port 7 I/O Data Register)
(Address: 07h)
Bits 7~0: 8-bit I/O registers of Port 7
User can use the IOC70 register to define each bit either as input or output.
RBS1
Bit 7
Bit 7
Bit 7
Bit 7
R57
R67
R77
IOCPAGE = “0” : Page 0 (select register of IOC 50 to IOC F0)
IOCPAGE = “1” : Page 1 (select register of IOC 61 to IOC E1)
See the data memory configuration in Fig. 6-2. Use the BANK instruction (e.g.
BABK 1) to change banks.
indirect addressing mode. If no indirect addressing is used, the RSR can be used
as an 8-bit general purpose read/writer register.
RBS0
Bit 6
Bit 6
R56
Bit 6
Bit 6
R66
R76
RSR5
Bit 5
R55
Bit 5
Bit 5
Bit 5
R65
R75
Bit 4
RSR4
R54
Bit 4
Bit 4
Bit 4
R64
R74
Bit 3
RSR3
Bit 3
Bit 3
Bit 3
R63
R73
−
Bit 2
RSR2
Bit 2
Bit 2
Bit 2
R62
R72
−
8-Bit Microcontroller
Bit 1
RSR1
Bit 1
Bit 1
Bit 1
R61
−
R71
EM78P468N/L
IOCPAGE
Bit 0
RSR0
Bit 0
Bit 0
Bit 0
R60
R70
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