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Semiconductor Group
20
Memory Organization
For details about the addressing modes see chapter 9.1.
Figure 4-1
Program Memory Address Space
The lower 128 bytes of the internal RAM are again grouped in three address spaces
(see figure 4-3):
1)
A general purpose register area occupies locations 0 through 1FH (see also section 4.3).
2)
The next 16 bytes, location 20H through 2FH, contain 128 directly addressable bits.
Programming information: These bits can be referred to in two ways, both of which are
acceptable for the ASM51. One way is to refer to their bit addresses, i.e. 0 to 7FH. The other
way is by referencing to bytes 20H to 2FH. Thus bits 0 to 7 can also be referred to as bits 20.0
to 20.7, and bits 08H and 0FH are the same as 21.0 to 21.7 and so on. Each of the 16 bytes in
this segment may also be addressed as a byte.)
3)
Locations 30H to 7FH can be used as a scratch pad area.
Address Space
Locations
Addressing Mode
Lower 128 bytes of RAM
00H to 7FH
direct/indirect
Upper 128 bytes of RAM
80H to 0FFH
indirect
Special function registers
80H to 0FFH
direct
*
Summary of Contents for SAB 80515 Series
Page 9: ...Semiconductor Group 9 Introduction Figure 1 2 Block Diagram ...
Page 12: ...Semiconductor Group 12 Fundamental Structure Figure 2 1 Detailed Block Diagram ...
Page 18: ...Semiconductor Group 18 Central Processing Unit Figure 3 1 Fetch Execute Sequence ...
Page 73: ...Semiconductor Group 73 On Chip Peripheral Components Figure 7 25 A D Converter Block Diagram ...
Page 83: ...Semiconductor Group 83 On Chip Peripheral Components Figure 7 33 a Timer 2 Block Diagram ...
Page 215: ...Device Specifications Semiconductor Group 215 ...
Page 217: ...Device Specifications Semiconductor Group 217 Pin Configuration P LCC 68 ...
Page 219: ...Device Specifications Semiconductor Group 219 Logic Symbol ...
Page 226: ...Device Specifications Semiconductor Group 226 Figure 1 Block Diagram ...
Page 229: ...Device Specifications Semiconductor Group 229 Figure 2 Memory Address Spaces ...
Page 239: ...Device Specifications Semiconductor Group 239 Figure 4 Block Diagram of the A D Converter ...
Page 241: ...Device Specifications Semiconductor Group 241 Figure 5 Interrupt Request Sources ...
Page 242: ...Device Specifications Semiconductor Group 242 Figure 6 Interrupt Priority Level Structure ...