ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 344

• Manufacturer Part Number: ATMEGA325-16AJ
• Description: 8-bit Microcontroller with In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

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ATmega325/3250/645/6450
JTAG Interface and On-chip Debug System ................................. 210
IEEE 1149.1 (JTAG) Boundary-scan .............................................. 216
Boot Loader Support – Read-While-Write Self-Programming ..... 242
Memory Programming..................................................................... 256
Electrical Characteristics................................................................ 286
Overview........................................................................................................... 210
Test Access Port – TAP.................................................................................... 210
TAP Controller .................................................................................................. 212
Using the Boundary-scan Chain ....................................................................... 213
Using the On-chip Debug System .................................................................... 213
On-chip Debug Specific JTAG Instructions ...................................................... 214
On-chip Debug Related Register in I/O Memory .............................................. 215
Using the JTAG Programming Capabilities ...................................................... 215
Bibliography ...................................................................................................... 215
Features............................................................................................................ 216
System Overview.............................................................................................. 216
Data Registers .................................................................................................. 216
Boundary-scan Specific JTAG Instructions ...................................................... 218
Boundary-scan Related Register in I/O Memory .............................................. 219
Boundary-scan Chain ....................................................................................... 220
ATmega325/3250/645/6450 Boundary-scan Order.......................................... 229
Boundary-scan Description Language Files ..................................................... 241
Boot Loader Features ....................................................................................... 242
Application and Boot Loader Flash Sections .................................................... 242
Read-While-Write and No Read-While-Write Flash Sections........................... 242
Boot Loader Lock Bits....................................................................................... 244
Entering the Boot Loader Program ................................................................... 245
Addressing the Flash During Self-Programming .............................................. 247
Self-Programming the Flash ............................................................................. 248
Program And Data Memory Lock Bits .............................................................. 256
Fuse Bits........................................................................................................... 257
Signature Bytes ................................................................................................ 259
Calibration Byte ................................................................................................ 259
Parallel Programming Parameters, Pin Mapping, and Commands .................. 259
Serial Programming Pin Mapping ..................................................................... 261
Parallel Programming ....................................................................................... 262
Serial Downloading........................................................................................... 270
Programming via the JTAG Interface ............................................................... 274
Absolute Maximum Ratings*............................................................................. 286
DC Characteristics............................................................................................ 286
External Clock Drive Waveforms ...................................................................... 288
External Clock Drive ......................................................................................... 288
2570A–AVR–09/04