Boot Loader Support – Read-While-Write Self-Programming..... 206
Boot Loader Features....................................................................................... 206
Application and Boot Loader Flash Sections.................................................... 206
Read-While-Write and No Read-While-Write Flash Sections........................... 206
Boot Loader Lock Bits....................................................................................... 208
Entering the Boot Loader Program................................................................... 209
Addressing the Flash During Self-Programming .............................................. 211
Self-Programming the Flash............................................................................. 212
Memory Programming..................................................................... 219
Program And Data Memory Lock Bits .............................................................. 219
Fuse Bits........................................................................................................... 220
Signature Bytes ................................................................................................ 221
Calibration Byte ................................................................................................ 221
Parallel Programming Parameters, Pin Mapping, and Commands .................. 222
Parallel Programming ....................................................................................... 224
Serial Downloading........................................................................................... 232
Serial Programming Pin Mapping..................................................................... 232
Electrical Characteristics................................................................ 237
Absolute Maximum Ratings*............................................................................. 237
DC Characteristics............................................................................................ 237
External Clock Drive Waveforms...................................................................... 239
External Clock Drive ......................................................................................... 239
Two-wire Serial Interface Characteristics ......................................................... 240
SPI Timing Characteristics ............................................................................... 241
ADC Characteristics ......................................................................................... 243
ATmega8 Typical Characteristics .................................................. 244
Register Summary........................................................................... 282
Instruction Set Summary ................................................................ 284
Ordering Information....................................................................... 287
Packaging Information.................................................................... 288
32A ................................................................................................................... 288
28P3 ................................................................................................................. 289
32M1-A ............................................................................................................. 290
Erratas .............................................................................................. 291
ATmega8
Rev. D, E, F, and G .......................................................................................... 291
4
ATmega8(L)
2486M–AVR–12/03
ATMEL [ ATMEL ]
