Manual

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AT89C5131
4136A–USB–03/03
In-System Programming (ISP) ........................................................... 53
Flash Programming and Erasure........................................................................ 54
Low Pin Count Boot Process.............................................................................. 55
High Pin-Count Boot Process............................................................................. 56
Application Programming Interface......................................................................58
Application Remarks........................................................................................... 58
XROW Bytes....................................................................................................... 59
Hardware Byte.................................................................................................... 60
On-chip Expanded RAM (XRAM) ....................................................... 61
Timer 2 ................................................................................................. 64
Auto-reload Mode ............................................................................................... 64
Programmable Clock Output .............................................................................. 65
Programmable Counter Array (PCA) ................................................ 69
PCA Capture Mode............................................................................................. 76
16-bit Software Timer/Compare Mode................................................................ 76
High Speed Output Mode ................................................................................... 77
Pulse Width Modulator Mode.............................................................................. 78
PCA Watchdog Timer......................................................................................... 79
Serial I/O Port ...................................................................................... 80
Framing Error Detection ..................................................................................... 80
Automatic Address Recognition.......................................................................... 81
Baud Rate Selection for UART for Mode 1 and 3............................................... 83
UART Registers.................................................................................................. 86
Interrupt System ................................................................................. 90
Overview............................................................................................................. 90
Registers............................................................................................................. 91
Interrupt Sources and Vector Addresses.............................................................98
Keyboard Interface ............................................................................. 99
Introduction......................................................................................................... 99
Description.......................................................................................................... 99
Registers........................................................................................................... 100
Programmable LED .......................................................................... 103
Serial Peripheral Interface (SPI) ...................................................... 104
Features............................................................................................................ 104
Signal Description............................................................................................. 104
Functional Description ...................................................................................... 106
USB Controller .................................................................................. 113