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7540 Group User’s Manual
iii
Table of contents
2.9 Oscillation control.............................................................................................................2-135
2.9.1 Memory map ...............................................................................................................2-135
2.9.2 Relevant registers ......................................................................................................2-135
2.9.3 Application example of ring oscillator .....................................................................2-137
2.9.4 Oscillation stop detection circuit ..............................................................................2-139
2.9.5 State transition ...........................................................................................................2-142
2.9.6 Notes on oscillation stop detection circuit..............................................................2-145
CHAPTER 3 APPENDIX
3.1 Electrical characteristics .....................................................................................................3-2
3.1.1 7540 Group (General purpose) ....................................................................................3-2
3.1.2 7540Group (Extended operating temperature version) ...........................................3-13
3.1.3 7540Group (Extended operating temperature 125 °C version) .............................3-22
3.2 Typical characteristics .......................................................................................................3-31
3.2.1 Mask ROM version ......................................................................................................3-31
3.2.2 One Time PROM version............................................................................................3-52
3.3 Notes on use ........................................................................................................................3-73
3.3.1 Notes on input and output ports................................................................................3-73
3.3.2 Termination of unused pins ........................................................................................3-74
3.3.3 Notes on Timer.............................................................................................................3-75
3.3.4 Notes on Timer A ........................................................................................................3-75
3.3.5 Notes on timer 1 ..........................................................................................................3-75
3.3.6 Notes on Timer X ........................................................................................................3-76
3.3.7 Notes on timer Y and timer Z....................................................................................3-77
3.3.8 Notes on Serial I/O1....................................................................................................3-79
3.3.9 Notes on serial I/O2 ....................................................................................................3-81
3.3.10 Notes on A-D converter ............................................................................................3-82
3.3.11 Notes on oscillation stop detection circuit..............................................................3-83
3.3.12 Notes on CPU mode register...................................................................................3-85
3.3.13 Notes on interrupts ....................................................................................................3-86
3.3.14 Notes on RESET pin .................................................................................................3-87
3.3.15 Notes on programming ..............................................................................................3-88
3.3.16 Programming and test of built-in PROM version...................................................3-90
3.3.17 Handling of Power Source Pin.................................................................................3-90
3.3.18 Notes on built-in PROM version ..............................................................................3-91
3.4 Countermeasures against noise ......................................................................................3-92
3.4.1 Shortest wiring length..................................................................................................3-92
3.4.2 Connection of bypass capacitor across V
SS
line and V
CC
line...............................3-94
3.4.3 Wiring to analog input pins ........................................................................................3-95
3.4.4 Oscillator concerns.......................................................................................................3-95
3.4.5 Setup for I/O ports.......................................................................................................3-96
3.4.6 Providing of watchdog timer function by software ..................................................3-97
3.5 List of registers ...................................................................................................................3-98
3.6 Package outline .................................................................................................................3-120
3.7 Machine instructions ........................................................................................................3-122
3.8 List of instruction code ...................................................................................................3-133
3.9 SFR memory map..............................................................................................................3-134
3.10 Pin configurations...........................................................................................................3-135
3.11 Differences between 7540 Group and 7531 Group .................................................3-139