Unified Program And Debug Interface (Updi); Features; Overview - Microchip Technology megaAVR 0 Series Manual

29.

Unified Program and Debug Interface (UPDI)

29.1

Features

• Programming:
– External programming through UPDI 1-wire (1W) interface
•
•
•
• Debugging:
– Memory mapped access to device address space (NVM, RAM, I/O)
– No limitation on device clock frequency
– Unlimited number of user program breakpoints
– Two hardware breakpoints
– Run-time readout of CPU Program Counter (PC), Stack Pointer (SP), and Status register
(SREG) for code profiling
– Program flow control
•
– Non-intrusive run-time chip monitoring without accessing system registers
•
• Unified Programming and Debug Interface (UPDI):
– Built-in error detection with error signature readout
– Frequency measurement of internal oscillators using the Event System
29.2

Overview

The Unified Program and Debug Interface (UPDI) is a proprietary interface for external programming and
on-chip debugging of a device.
The UPDI supports programming of nonvolatile memory (NVM) space; FLASH, EEPROM, fuses, lockbits,
and the user row. In addition, the UPDI can access the entire I/O and data space of the device. See the
NVM controller documentation for programming via the NVM controller and executing NVM controller
commands.
Programming and debugging are done through the UPDI Physical interface (UPDI PHY), which is a 1-
wire UART-based half duplex interface using a dedicated pin for data reception and transmission.
Clocking of UPDI PHY is done by an internal oscillator. The UPDI access layer grants access to the bus
matrix, with memory mapped access to system blocks such as memories, NVM, and peripherals.
The Asynchronous System Interface (ASI) provides direct interface access to On-Chip Debugging (OCD),
NVM, and System Management features. This gives the debugger direct access to system information,
without requesting bus access.
©
2018 Microchip Technology Inc.
Uses a dedicated pin of the device for programming
No GPIO pins occupied during operation
Asynchronous Half-Duplex UART protocol towards the programmer
Go, Stop, Reset, Step Into
Monitor CRC status and sleep status
Unified Program and Debug Interface (UPDI)
Datasheet Preliminary
®
megaAVR 0-Series
DS40002015A-page 439