EM78P468NBQ EMC [ELAN Microelectronics Corp], EM78P468NBQ Datasheet - Page 14

• Manufacturer Part Number: EM78P468NBQ
• Description: 8-BIT Microcontroller
• Manufacturer: EMC [ELAN Microelectronics Corp]

EM78P468N
8-BIT Microcontroller
10 •
4.1 Op
4.1
4.1
4.1.3
.1
.2
R0 is not a physically implemented register. It is used as indirect addressing pointer. Any
instruction using R0 as register actually accesses t
Register (R4).
Increases by an external signal edge applied to TCC, or by the instruction cycle clock.
Written and read by the program as any other register.
* The structure is depicted in Fig. 3
* Generates 4K × 13 on-chip ROM addresses to the relative programming instruction
codes.
* "JMP" instruction allows direct loading of the low 10 program counter bits.
* "CALL" instruction loads the low 10 bits of the PC and PC+1, then push it into the stack.
* "RET'' ("RETL k", "RETI") instruction loads the program counter with the contents at the
top of stack.
* "MOV R2, A"
contents of the ninth and tenth bits do not change.
* "ADD R2, A" allows a relative address be added to the current PC.
* The most significa
the Status register (R3) upon execution of a "JMP'' or "CALL'' instruction.
erational Registers
R0/IAR (Indirect Addressing Register)
R1/TCC (Time Clock Counter)
R2/PC (Program Counter)
(Addr
(Address: 01h)
(Address: 02h)
ess: 00h)
allows the loading of an address from
nt bit (A10~A11) will be loaded with the conten
(This specification is subject to change without further notice)
Product Specification (V1.2) 03.15.2005
he data pointed by the RAM Select
the A register to the PC. The
t of bits PS0~PS1 in