попробуем на примере tiny13 и mega32
судя по разнице в описании (без поллитра в деталях не разобраться) через debugWire отладка контролируется на стороне AtmelStudio (видимо он одну точку останова переносит до бесконечности пока не возникает необходимость показать остановку пользователю, а в JTAG есть возможность затолкать набор точек в сам МК и ждать пока МК остановится
Спойлер
• JTAG (IEEE std. 1149.1 Compliant) Interface
• Boundary-scan Capabilities According to the IEEE std. 1149.1 (JTAG) Standard
• Debugger Access to:
– All Internal Peripheral Units
– Internal and External RAM
– The Internal Register File
– Program Counter
– EEPROM and Flash Memories
– Extensive On-chip Debug Support for Break Conditions, Including
– AVR Break Instruction
– Break on Change of Program Memory Flow
– Single Step Break
– Program Memory Breakpoints on Single Address or Address Range
– Data Memory Breakpoints on Single Address or Address Range
• Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG Interface
• On-chip Debugging Supported by AVR Studio®
Спойлер
• Complete Program Flow Control
• Emulates All On-chip Functions, Both Digital and Analog, except RESET Pin
• Real-time Operation
• Symbolic Debugging Support (Both at C and Assembler Source Level, or for Other HLLs)
• Unlimited Number of Program Break Points (Using Software Break Points)
• Non-intrusive Operation
• Electrical Characteristics Identical to Real Device
• Automatic Configuration System
• High-Speed Operation
• Programming of Non-volatile Memories
