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Table of Contents
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12.1 WATCHDOG TIMER (WDG) . . . . . . . . . . . . . . . . . . . .... . . . .... .... .. . . . . . . . . . . 37
12.2 16-BIT TIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... . ... 40
12.3 SERIAL PERIPHERAL INTERFACE (SPI) . .... . ... .. .. .. . . . . . . . ... .. .. . . ... . 58
12.4 I2C BUS INTERFACE (I2C) . . . . . . . . . . . . . .... .... .. . .... .. . . . . . . ... .. . .... 71
12.5 8-BIT A/D CONVERTER (ADC) .... ... . . . .... . . . ... . . . . . . . . . . . . . ... ... . . . . 84
13 INSTRUCTION SET . . . . . . . . . . . . . . . . . . . . . . . . .... . . . . .. . . . . . . . . . . . . . ... .. . .... 88
13.1 ST7 ADDRESSING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
13.2 INSTRUCTION GROUPS . . . . . . . . . . . . . . . . . . . . . .... .... ... . . . . . . . . ... .. . . . 91
14 ELECTRICAL CHARACTERISTICS . . . . .... .. . .... . ... .. .. .. .... . . . ... . . . . . . . . . . 94
14.1 PARAMETER CONDITIONS . . . . . . . . . . . . . . . . . . . .... .... ... . . . . . . . . ... .. . . . 94
14.2 ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
14.3 OPERATING CONDITIONS . . . . . . . . . . . . . .... .... .. . .... .. . . . . . . ... .. . . . . . 96
14.4 SUPPLY CURRENT CHARACTERISTICS . . . .... ... . ... . . .. .. .. .. . . . . . . ... .. 99
14.5 CLOCK AND TIMING CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . .... . . ... . 102
14.6 MEMORY CHARACTERISTICS . . . . . . ... .. ... .. .. . . . . . . . ... .. .. .... . . ... . 109
14.7 EMC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
14.8 I/O PORT PIN CHARACTERISTICS . . . ... .. .... ... . ... . . .. .. .. .. . . . . . . ... . 115
14.9 CONTROL PIN CHARACTERISTICS . . . . . . . . ... . . . . ... .. ... .. .. . . . . . . . ... . 118
14.10 TIMER PERIPHERAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . .... . . . 121
14.11 COMMUNICATION INTERFACE CHARACTERISTICS . . . . . .... .... .. . . . . . . . . . 122
14.12 8-BIT ADC CHARACTERISTICS . . . . . . . . .... . ... .. . . . . .... . . . ... . . . . . . . . . 125
15 PACKAGE CHARACTERISTICS . . . . . . .... .. . .... . ... .. .. .. .... . . . ... . . . . . . . . . 127
15.1 PACKAGE MECHANICAL DATA . . . . . . . . . . . . . . . .... .... ... . ... .. . . ... .. . . 127
15.2 THERMAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . .... .... .. . . . . . . . . . 128
15.3 SOLDERING AND GLUEABILITY INFORMATION . . . . . . . . . . . . . . . . . . . . . .... . . . 129
15.4 PACKAGE/SOCKET FOOTPRINT PROPOSAL . . . . . . . . . . . .... .... .. . . . . . . . . . 129
16 DEVICE CONFIGURATION AND ORDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . 130
16.1 OPTION BYTES . . . .... .... .. . . . . . . . . .... . ... .. .. .. . .... ... . . . . . . . . . . . 130
16.2 DEVICE ORDERING INFORMATION AND TRANSFER OF CUSTOMER CODE . . . . 131
16.3 DEVELOPMENT TOOLS . . . . . . . . . . . . . . . . . . . . . .... . . . . ... . ... .. . . ... .. . . 133
16.4 ST7 APPLICATION NOTES . . . . . . . . . . . . . . . ... . . . . . . . . . .... ... . . . . . . . . . . . 134
16.5 TO GET MORE INFORMATION . . . . . . ... . . . . . . . . . ... .. .. ... .. .. . . .. . . ... . 134
17 SUMMARY OF CHANGES . .... . . .. .. .. .. . . . . . . . . . . . . . ... . . . . . . . . . ... .. .. ... . 135