Datasheet

 2018 Microchip Technology Inc. Data Sheet Complete DS40002070A-page 8
ATmega164A/PA/324A/PA/644A/PA/1284/P
25.2 Overview........................................................................................................ 268
25.3 Data Registers............................................................................................... 269
25.4 Boundary-scan Specific JTAG Instructions ................................................... 270
25.5 Boundary-scan Chain .................................................................................... 271
25.6 ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P Boundary-scan order 274
25.7 Boundary-scan Description Language Files.................................................. 275
25.8 Register description....................................................................................... 276
26 Boot loader support – read-while-write self-programming ..................... 277
26.1 Features ........................................................................................................ 277
26.2 Overview........................................................................................................ 277
26.3 Application and Boot Loader Flash Sections................................................. 277
26.4 Read-While-Write and No Read-While-Write Flash Sections........................ 278
26.5 Boot Loader Lock Bits ................................................................................... 280
26.6 Entering the Boot Loader Program................................................................ 281
26.7 Addressing the Flash During Self-Programming ........................................... 282
26.8 Self-Programming the Flash.......................................................................... 283
26.9 Register description....................................................................................... 293
27 Memory programming .................................................................................................... 295
27.1 Program And Data Memory Lock Bits ........................................................... 295
27.2 Fuse bits ........................................................................................................ 296
27.3 Signature Bytes ............................................................................................. 298
27.4 Calibration byte.............................................................................................. 298
27.5 Page Size ...................................................................................................... 298
27.6 Parallel Programming Parameters, Pin Mapping, and Commands ............... 299
27.7 Parallel programming .................................................................................... 301
27.8 Serial downloading ........................................................................................ 309
27.9 Serial Programming Instruction set ............................................................... 312
27.10 Programming via the JTAG Interface ............................................................ 314
28 Electrical characteristics (TA = -40°C to 85°C) ................................................ 326
28.1 DC Characteristics......................................................................................... 326
28.2 Speed grades ................................................................................................ 332
28.3 Clock characteristics...................................................................................... 333
28.4 System and reset characteristics................................................................... 334
28.5 External interrupts characteristics ................................................................. 334
28.6 SPI timing characteristics .............................................................................. 335