Contents
Contents
1
2
3
General Description ......................................................................................1
Features .........................................................................................................1
Pin Assignments and Descriptions..............................................................2
3.1 Pin Assignments................................................................................................. 2
3.2 Pin Descriptions ................................................................................................. 3
3.2.1 EM78P157NBP and EM78P157NBM Pin Descriptions......................................3
3.2.2 EM78P157NAP and EM78P157NAM Pin Descriptions......................................3
3.2.3 EM78P157NAAS Pin Descriptions......................................................................4
3.2.4 EM78P157NAKM Pin Descriptions.....................................................................4
4
Function Description.....................................................................................5
4.1 Operational Registers......................................................................................... 5
4.1.1 Indirect Addressing (R0) Register .......................................................................6
4.1.2 Time Clock / Counter (R1) Register....................................................................6
4.1.3 Program Counter and Stack (R2) Register .........................................................6
4.1.4 Status (R3) Register............................................................................................7
4.1.5 RAM Select (R4) Register...................................................................................7
4.1.6 Port 5 ~ Port 6 (R5 ~ R6) Registers....................................................................8
4.1.7 Interrupt Status (RF) Register .............................................................................8
4.1.8 General Purpose (R10 ~ R3F) Registers............................................................8
4.2 Special Purpose Registers ................................................................................. 8
4.2.1 Accumulator (A) Register....................................................................................8
4.2.2 Control (CONT ) Register....................................................................................9
4.2.3 I/O Port Control (IOC5 ~ IOC6) Registers...........................................................9
4.2.4 Prescaler Counter (IOCA ) Register....................................................................9
4.2.5 Pull-Down Control (IOCB) Register...................................................................10
4.2.6 Open-Drain Control (IOCC ) Register ...............................................................10
4.2.7 Pull-High Control (IOCD) Register ....................................................................11
4.2.8 WDT Control (IOCE) Register...........................................................................11
4.2.9 IOCF (Interrupt Mask Register).........................................................................12
4.3 TCC/WDT & Prescaler ..................................................................................... 12
4.4 I/O Ports ........................................................................................................... 13
4.4.1 Port 6 Input Change Wake-up/Interrupt Function Usage..................................16
4.5 RESET and Wake-up ....................................................................................... 17
4.5.1 Summary of Initialized Values for Registers......................................................19
4.5.2 The Status of RST, T, and P of STATUS Register.............................................21
4.5.2.1 RST, T and P after RESET Values .....................................................21
4.5.2.2 Event Affecting T and P Status...........................................................21
4.6 Interrupt............................................................................................................ 22
Product Specification (V1.0) 09.22.2005
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ELAN [ ELAN MICROELECTRONICS CORP ]
