em78p131a ELAN Microelectronics Corp, em78p131a Datasheet - Page 8

• Manufacturer Part Number: em78p131a
• Description: 8-bit Microcontroller With Otp Rom
• Manufacturer: ELAN Microelectronics Corp

EM78P131A
8-Bit Microcontroller with OTP ROM
5
4 •
Functional Description
5.1 Operational Registers
5.1.1 R0 (Indirect Addressing Register)
R0 is not a physically implemented register. It is used as an indirect addressing
pointer. Any instruction using R0 as a pointer actually accesses data pointed by the
RAM Select Register (R4).
5.1.2 R1 (Timer Clock /Counter)
Incremented by an external signal edge, which is defined by TE bit (CONT-4)
through the TCC pin, or by the instruction cycle clock.
Writable and readable as any other registers.
Defined by resetting PAB (CONT-3).
Figure 5-1 EM78P131A Functional Block Diagram
(This specification is subject to change without further notice)
Product Specification (V1.2) 09.16.2009