Microchip Technology ATAVRISP2

Overview

ATAVRISP2 from Microchip Technology (formerly Atmel) is a USB-based in-system programmer for AVR 8-bit microcontrollers, supporting ISP programming via SPI interface with configurable SCK frequency up to 8 MHz, target voltage monitoring (0–5.5 V), and firmware-upgradable operation. It enables flash, EEPROM, fuse, lock bit, and signature byte programming across the full ATmega, ATtiny, and AT90 families.

For engineers reviewing the ATAVRISP2 datasheet, ATAVRISP2 pinout, ATAVRISP2 application, or ATAVRISP2 equivalent, key selection considerations include USB 2.0 full-speed compatibility (12 Mbps), support for both active-high (AT89) and active-low (AVR) reset polarity, real-time target connection status reporting (e.g., MOSI/RST/SCK continuity), and XML-driven device-specific programming parameters embedded in AVR Studio toolchain.

Technical Context

The ATAVRISP2 implements a vendor-class USB device (bDeviceClass = 0xFF) with one interface, two bulk endpoints (64-byte max packet size), and self-powered operation (200 mA). Its firmware executes a deterministic command-response protocol over USB, where each host command triggers a defined answer ID and status code (e.g., STATUS_CMD_OK, STATUS_CMD_TOUT).

Programming logic is driven by XML part description files defining device-specific timing (stabDelay, eraseDelay), polling methods (RDY/BSY or value polling), and ISP command sequences (e.g., CMD_ENTER_PROGMODE_ISP with configurable synchLoops and cmdexeDelay). All low-level SPI transactions-including multi-byte flash page writes and fuse reads-are abstracted through 23 standardized commands mapped to fixed byte IDs (e.g., CMD_PROGRAM_FLASH_ISP = 0x13).

Key Specifications

Availability

ATAVRISP2 is available at Aetrix Electronics and suitable for AVR microcontroller development, production programming, and field firmware updates requiring stable component supply, consistent ISP timing behavior, and long-term toolchain compatibility with legacy AVR Studio workflows.

Supply support for ATAVRISP2 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology acquired Atmel in 2016 and maintains legacy AVR tooling including the ATAVRISP2. The company specializes in microcontrollers, analog, FPGA, and development tools for industrial, automotive, and IoT applications.

The ATAVRISP2 belongs to Atmel's legacy AVR In-System Programming (ISP) tool family, designed specifically to deliver reliable, low-cost, USB-connected programming for 8-bit AVR microcontrollers in engineering labs and small-batch manufacturing environments.

FAQ

What is the primary function of the ATAVRISP2?

The ATAVRISP2 is a dedicated USB-based in-system programmer for AVR 8-bit microcontrollers. It performs ISP programming via SPI-writing and verifying flash, EEPROM, fuses, lock bits, and signature bytes-while providing real-time target connection diagnostics and configurable clock timing. The ATAVRISP2 does not operate as a debugger or emulator; its role is strictly programming and verification.

Does the ATAVRISP2 require a specific driver to operate on Windows?

Yes, the ATAVRISP2 requires the Jungo WinDriver licensed and bundled with AVR Studio 4.12 or later. This driver enables communication with the vendor-class USB device (idVendor=0x03EB, idProduct=0x2104). Third-party tools must use the same driver instance; switching drivers disrupts concurrent access between AVR Studio and other utilities. The ATAVRISP2 will not enumerate correctly without this driver installed.

Can the ATAVRISP2 program non-AVR microcontrollers like the AT89 series?

Yes, the ATAVRISP2 supports both AVR and AT89 (8051-family) microcontrollers. It achieves this through programmable reset polarity (PARAM_RESET_POLARITY = 1 for AVR active-low, 0 for AT89 active-high) and device-specific XML configuration files that define timing, command sequences, and polling behavior. The ATAVRISP2 uses identical command protocol (e.g., CMD_ENTER_PROGMODE_ISP) but adapts execution per target family.

How does the ATAVRISP2 handle target devices with flash memory larger than 64 KB?

The ATAVRISP2 handles >64 KB flash using extended addressing: when bit 31 of the CMD_LOAD_ADDRESS parameter is set, it signals the need for a load-extended-address operation before subsequent flash read/write commands. This mechanism is defined in AVR device datasheets and implemented in the ATAVRISP2 firmware to support word-addressed memories beyond the 16-bit limit. The ATAVRISP2 itself does not modify address width-it relies on host software (e.g., AVR Studio) to issue the correct sequence.

Is firmware upgrade supported for the ATAVRISP2, and how is it performed?

Yes, firmware upgrades are supported exclusively via the CMD_FIRMWARE_UPGRADE command (ID 0x07), which triggers a controlled reboot into bootloader mode. The upgrade process requires the official AVR Studio–bundled utility and the Jungo driver. No field-upgrade capability exists outside this workflow; attempting manual firmware injection or third-party tools will brick the unit. The ATAVRISP2 reports current version via PARAM_SW_MAJOR/PARAM_SW_MINOR and hardware revision via PARAM_HW_VER.