UPD77016 NEC, UPD77016 Datasheet - Page 19

• Manufacturer Part Number: UPD77016
• Description: 16 bits/ Fixed-point Digital Signal Processor
• Manufacturer: NEC

2.4.1 Instruction RAM Outline
of the instruction RAM. Internal RAM is initialized and rewritten by boot program.
instruction memory. When RAM is used as the external memory, it can be initialized and rewritten by boot
program.
2.4.2 Data Memory Outline
available as the PD77016 has interface with the external data memory.
2.4.3 Data Memory Addressing
The PD77016 has an instruction RAM (1.5 words
Additionally external memory expansion is available as the
Boot up ROM contains the program loading instruction code to internal and external instruction RAM.
When the external instruction memory area is accessed, instruction cycle can be 2 or more by wait function.
The PD77016 has two data memory areas (64 words
Each memory areas consists of 2K words
Each data memory area includes on-chip peripheral area which consists of 64 words.
When the external data memory area is accessed, instruction cycle can be 2 or more by wait function.
There are following two types of data memory addressing.
• Direct addressing
• Indirect addressing
The address is specified in the instruction field.
The address is specified by the data pointer (DP). DP can get a bit reverse before addressing. It can update
the DP value after accessing data memory.
16 bits data RAM. Additionally, data memory expansion is
32 bits). A system vector area is assigned to 64 words
16 bits each) in X and Y memory areas.
PD77016 has interface with the external
PD77016
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