Atmel Atmel-ICE User manual

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USER GUIDE
Atmel-ICE
The Atmel-ICE Debugger
Atmel-ICE is a powerful development tool for debugging and programming
ARM® Cortex®-M based Atmel® SAM and Atmel AVR® microcontrollers with On-
Chip Debug capability.
It supports:
●Programming and on-chip debugging of all Atmel AVR 32-bit
microcontrollers on both JTAG and aWire interfaces
●Programming and on-chip debugging of all Atmel AVR XMEGA® family
devices on both JTAG and PDI 2-wire interfaces
●Programming (JTAG and SPI) and debugging of all Atmel AVR 8-bit
microcontrollers with OCD support on either JTAG or debugWIRE interfaces
●Programming and debugging of all Atmel SAM ARM Cortex-M based
microcontrollers on both SWD and JTAG interfaces
●Programming (TPI) of all Atmel tinyAVR® 8-bit microcontrollers with support
for this interface
Consult the supported devices list in the Atmel Studio User Guide for a full list of
devices and interfaces supported by this firmware release.

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Table of Contents
The Atmel-ICE Debugger ............................................................. 1
1. Introduction .............................................................................. 4
1.1. Introduction to the Atmel-ICE ................................................... 4
1.2. Atmel-ICE Features ............................................................... 4
1.3. System Requirements ............................................................ 4
2. Getting Started with the Atmel-ICE ......................................... 6
2.1. Full Kit Contents ................................................................... 6
2.2. Basic Kit Contents ................................................................. 6
2.3. PCBA Kit Contents ................................................................ 7
2.4. Spare Parts Kits .................................................................... 7
2.5. Kit Overview ......................................................................... 8
2.6. Assembling the Atmel-ICE ...................................................... 8
2.7. Opening the Atmel-ICE ......................................................... 10
2.8. Powering the Atmel-ICE ........................................................ 12
2.9. Connecting to the Host Computer ........................................... 12
2.10. USB Driver Installation ......................................................... 12
2.10.1. Windows ................................................................ 12
3. Connecting the Atmel-ICE .................................................... 13
3.1. Overview: Connecting to AVR and SAM Target Devices .............. 13
3.2. Connecting to a JTAG Target ................................................. 13
3.3. Connecting to an aWire Target ............................................... 14
3.4. Connecting to a PDI Target ................................................... 15
3.5. Connecting to a debugWIRE Target ........................................ 15
3.6. Connecting to a SPI Target ................................................... 16
3.7. Connecting to a TPI Target .................................................... 17
3.8. Connecting to a SWD Target ................................................. 17
4. On-Chip Debugging .............................................................. 19
4.1. Introduction to On-Chip Debugging (OCD) ................................ 19
4.2. Physical Interfaces ............................................................... 19
4.2.1. JTAG ..................................................................... 19
4.2.2. aWire .................................................................... 21
4.2.3. PDI Physical ........................................................... 22
4.2.4. debugWIRE ............................................................ 22
4.2.5. SPI ....................................................................... 22
4.2.6. TPI ....................................................................... 23
4.2.7. SWD ..................................................................... 23
4.3. Atmel OCD Implementations .................................................. 23
4.3.1. Atmel AVR UC3 OCD (JTAG and aWire) ...................... 23
4.3.2. Atmel AVR XMEGA OCD (JTAG and PDI Physical) ........ 24
4.3.3. Atmel megaAVR OCD (JTAG) .................................... 24
4.3.4. Atmel megaAVR / tinyAVR OCD (debugWIRE) .............. 24
4.3.5. ARM Coresight Components ..................................... 24
5. Hardware Description ............................................................ 25
5.1. LEDs ................................................................................. 25
5.2. Rear Panel ......................................................................... 25
5.3. Bottom Panel ...................................................................... 25
5.4. Architecture Description ........................................................ 26
5.4.1. Atmel-ICE Mainboard ............................................... 26
5.4.2. Atmel-ICE Target Connectors ..................................... 27
5.4.3. Atmel-ICE target Connectors Part Numbers .................. 27
6. Software Integration .............................................................. 28
6.1. Atmel Studio ....................................................................... 28
6.1.1. Software Integration in Atmel Studio ............................ 28
6.1.2. Programming Options ............................................... 28
6.1.3. Debug Options ........................................................ 28

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7. Command Line Utility ............................................................ 30
8. Advanced Debugging Techniques ........................................ 31
8.1. Atmel AVR UC3 Targets ....................................................... 31
8.1.1. EVTI / EVTO Usage ................................................. 31
8.2. debugWIRE Targets ............................................................. 31
8.2.1. Software Breakpoints ............................................... 31
9. Special Considerations ......................................................... 32
9.1. Atmel AVR XMEGA OCD ...................................................... 32
9.2. Atmel megaAVR OCD and debugWIRE OCD ............................ 32
9.2.1. Atmel megaAVR OCD (JTAG) .................................... 33
9.2.2. debugWIRE OCD .................................................... 34
9.3. Atmel AVR UC3 OCD ........................................................... 35
9.4. SAM / Coresight OCD .......................................................... 35
10. Firmware Upgrade ................................................................ 37
11. Release History and Known issues ...................................... 38
11.1. What's New ........................................................................ 38
11.2. Firmware Release History ..................................................... 38
11.2.1. Atmel Studio 6.2 ..................................................... 38
11.2.2. Atmel Studio 6.2 (beta)2 ........................................... 38
11.3. Known Issues Concerning the Atmel-ICE ................................. 38
11.3.1. Atmel AVR XMEGA OCD Specific Issues ..................... 38
11.3.2. Atmel megaAVR OCD and Atmel tinyAVR OCD
Specific Issues ........................................................ 38
11.4. Device Support ................................................................... 38
12. Product Compliance .............................................................. 39
12.1. RoHS and WEEE ................................................................ 39
12.2. CE and FCC ...................................................................... 39
13. Document Revisions ............................................................. 40

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1. Introduction
1.1 Introduction to the Atmel-ICE
Atmel-ICE is a powerful development tool for debugging and programming ARM Cortex-M based Atmel SAM
and Atmel AVR microcontrollers with On-Chip Debug capability.
It supports:
●Programming and on-chip debugging of all Atmel AVR UC3 microcontrollers on both JTAG and aWire
interfaces
●Programming and on-chip debugging of all AVR XMEGA family devices on both JTAG and PDI 2-wire
interfaces
●Programming (JTAG and SPI) and debugging of all AVR 8-bit microcontrollers with OCD support on both
JTAG or debugWIRE interfaces
●Programming and debugging of all Atmel SAM ARM Cortex-M based microcontrollers on both SWD and
JTAG interfaces
●Programming (TPI) of all Atmel tinyAVR 8-bit microcontrollers with support for this interface
1.2 Atmel-ICE Features
●Fully compatible with Atmel Studio
●Supports programming and debugging of all Atmel AVR UC3 32-bit microcontrollers
●Supports programming and debugging of all 8-bit AVR XMEGA devices
●Supports programming and debugging of all 8-bit Atmel megaAVR® and tinyAVR devices with OCD
●Supports programming and debugging of all SAM ARM Cortex-M based microcontrollers
●Target operating voltage range of 1.62V to 5.5V
●Draws less than 3mA from target VTref when using debugWIRE interface and less than 1mA for all other
interfaces
●Supports JTAG clock frequencies from 32kHz to 7.5MHz
●Supports PDI clock frequencies from 32kHz to 7.5MHz
●Supports debugWIRE baud rates from 4kbit/s to 0.5Mbit/s
●Supports aWire baud rates from 7.5kbit/s to 7Mbit/s
●Supports SPI clock frequencies from 8kHz to 5MHz
●Supports SWD clock frequencies from 32kHz to 2MHz
●USB 2.0 high-speed host interface
●ITM serial trace capture at up to 3MB/s
●Supports 10-pin 50-mil JTAG connector with both AVR and Cortex pinouts. The standard probe cable
supports AVR 6-pin ISP/PDI/TPI 100-mil headers as well as 10-pin 50-mil. An adapter is available to
support 6-pin 50-mil, 10-pin 100-mil and 20-pin 100-mil headers. Several kit options are available with
different cabling and adapters.
1.3 System Requirements
The Atmel-ICE unit requires that a front-end debugging environment Atmel Studio version 6.2 or later is
installed on your computer.

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The Atmel-ICE should be connected to the host computer using the USB cable provided, or a certified USB-
micro cable.

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2. Getting Started with the Atmel-ICE
2.1 Full Kit Contents
The Atmel-ICE full kit contains these items:
●Atmel-ICE unit
●USB cable (1.8m, high-speed, micro-B)
●Adapter board containing 50-mil AVR, 100-mil AVR/SAM and 100-mil 20-pin SAM adapters
●IDC flat cable with 10-pin 50-mil connector and 6-pin 100-mil connector
●50-mil 10-pin mini squid cable with 10 x 100-mil sockets
Figure 2-1. Atmel-ICE Full Kit Contents
2.2 Basic Kit Contents
The Atmel-ICE basic kit contains these items:
●Atmel-ICE unit
●USB cable (1.8m, high-speed, micro-B)
●IDC flat cable with 10-pin 50-mil connector and 6-pin 100-mil connector

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Figure 2-2. Atmel-ICE Basic Kit Contents
2.3 PCBA Kit Contents
The Atmel-ICE PCBA kit contains these items:
●Atmel-ICE unit without plastic encaptulation
Figure 2-3. Atmel-ICE PCBA Kit Contents
2.4 Spare Parts Kits
The following spare parts kits are available:
●Adapter kit
●Cable kit

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Figure 2-4. Atmel-ICE Adapter Kit Contents
Figure 2-5. Atmel-ICE Cable Kit Contents
2.5 Kit Overview
The Atmel-ICE kit options are shown diagrammatically here:
Figure 2-6. Atmel-ICE Kit Overview
PCBA
PCBA kit
basic kit
adapter kit
full kit
SAM AVR
cable kit
2.6 Assembling the Atmel-ICE
The Atmel-ICE unit is shipped with no cables attached. Two cable options are provided in the full kit:
●50-mil 10-pin IDC flat cable with 6-pin ISP and 10-pin connectors

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●50-mil 10-pin mini-squid cable with 10 x 100-mil sockets
Figure 2-7. Atmel-ICE Cables
For most purposes, the 50-mil 10-pin IDC flat cable can be used, connecting either natively to its 10-pin or 6-
pin connectors, or connecting via the adapter board. Three adapters are provided on one small PCBA. The
following adapters are included:
●100-mil 10-pin JTAG/SWD adapter
●100-mil 20-pin SAM JTAG/SWD adapter
●50-mil 6-pin SPI/debugWIRE/PDI/aWire adapter
Figure 2-8. Atmel-ICE Adapters
Note A 50-mil JTAG adapter has not been provided - this is because the 50-mil 10-pin IDC cable can
be used to connect directly to a 50-mil JTAG header. For the part number of the component used
for the 50-mil 10-pin connector, see “Atmel-ICE target Connectors Part Numbers” on page 27.
The 6-pin ISP/PDI header is included as part of the 10-pin IDC cable. This termination can be cut off if it is not
required.
To assemble your Atmel-ICE into its default configuration, connect the 10-pin 50-mil IDC cable to the unit as
shown below. Be sure to orient the cable so that the red wire (pin 1) on the cable aligns with the triangular
indicator on the blue belt of the enclosure. The cable should connect upwards from the unit. Be sure to connect
to the port corresponding to the pinout of your target - AVR or SAM.
Figure 2-9. Atmel-ICE Cable Connection

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Figure 2-10. Atmel-ICE AVR Probe Connection
Figure 2-11. Atmel-ICE SAM Probe Connection
2.7 Opening the Atmel-ICE
Note For normal operation, the Atmel-ICE unit must not be opened. Opening the unit is done at your
own risk. Anti-static precautions should be taken.
The Atmel-ICE enclosure consists of three separate plastic components - top cover, bottom cover and blue
belt - which are snapped together during assembly. To open the unit, simply insert a large flat screwdriver into
the openings in the blue belt, apply some inward pressure and twist gently. Repeat the process on the other
snapper holes, and the top cover will pop off.

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Figure 2-12. Opening the Atmel-ICE (1)
Figure 2-13. Opening the Atmel-ICE (2)

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Figure 2-14. Opening the Atmel-ICE(3)
To close the unit again, simply align the top and bottom covers correctly, and press together firmly.
2.8 Powering the Atmel-ICE
The Atmel-ICE is powered by the USB bus voltage. It requires less than 100mA to operate, and can therefore
be powered through a USB hub. The power LED will illuminate when the unit is plugged in. When not
connected in an active programming or debugging session, the unit will enter low-power consumption mode to
preserve your computer's battery. The Atmel-ICE cannot be powered down - it should be unplugged when not
in use.
2.9 Connecting to the Host Computer
The Atmel-ICE communicates primarily using a standard HID interface, and does not require a special driver on
the host computer. To use the advanced data gateway functionality of the Atmel-ICE, be sure to install the USB
driver on the host computer. This is done automatically when installing the front-end software provided free by
Atmel. See www.atmel.com1 for further information or to download the latest front-end software.
The Atmel-ICE must be connected to an available USB port on the host computer using the USB cable
provided, or suitable USB certified micro cable. The Atmel-ICE contains a USB 2.0 compliant controller, and
can operate in both full-speed and high-speed modes. For best results, connect the Atmel-ICE directly to a
USB 2.0 compliant high-speed hub on the host computer using the cable provided.
2.10 USB Driver Installation
2.10.1 Windows
When installing the Atmel-ICE on a computer running Microsoft® Windows®, the USB driver is loaded when the
Atmel-ICE is first plugged in.
Note Be sure to install the front-end software packages before plugging the unit in for the first time.
Once successfully installed, the Atmel-ICE will appear in the device manager as a "Human Interface Device".
1 http://www.atmel.com/

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3. Connecting the Atmel-ICE
3.1 Overview: Connecting to AVR and SAM Target Devices
The Atmel-ICE probe has two 50-mil 10-pin JTAG connectors accessible on the front of the tool's enclosure.
Both connectors are directly electrically connected, but conform to two different pinouts - the AVR JTAG header
and the ARM Cortex Debug header. The connector should be selected based on the pinout of the target board,
and not the target MCU type - for example a SAM device mounted in a AVR STK600 stack should use the AVR
header.
Various cabling and adapters are available in the different Atmel-ICE kits. An overview of connection options is
shown.
Figure 3-1. Atmel-ICE Connection Options
6-pin 100-mil AVR ISP/
debugWIRE/PDI/aWire/
TPI header
10-pin 100-mil AVR
JTAG header
10-pin 50-mil AVR
JTAG header
SAM AVR
20-pin 100-mil SAM
header
(for EVKs etc)
10-pin 100-mil
JTAG/SWD header
10-pin 50-mil JTAG/SWD
(Cortex debug header)
SAM AVR
6-pin 50-mil AVR ISP/
debugWIRE/PDI/aWire/
TPI header
3.2 Connecting to a JTAG Target
The Atmel-ICE probe has two 50-mil 10-pin JTAG connectors accessible on the front of the tool's enclosure.
Both connectors are directly electrically connected, but conform to two different pinouts - the AVR JTAG header
and the ARM Cortex Debug header. The connector should be selected based on the pinout of the target board,
and not the target MCU type - for example a SAM device mounted in a AVR STK600 stack should use the AVR
header.
The recommended pinout for the 10-pin AVR JTAG connector is shown in Figure 4-2, “AVR JTAG Header
Pinout” on page 20.
The recommended pinout for the 10-pin ARM Cortex Debug connector is shown in Figure 4-3, “SAM JTAG
Header Pinout” on page 20.
Direct connection to a standard 10-pin 50-mil header
Use the 50-mil 10-pin flat cable (included in some kits) to connect directly to a board supporting this header
type. Use the AVR connector port on the Atmel-ICE for headers layed out in the AVR pinout, and the SAM
connector port for headers complying with the ARM Cortex Debug header pinout.
The pinouts for both 10-pin connector ports are shown below.
Connection to a standard 10-pin 100-mil header
Use a standard 50-mil to 100-mil adapter to connect to 100-mil headers. An adapter board (included in some
kits) can be used for this purpose, or alternatively the JTAGICE3 adapter can be used for AVR targets.

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Note The JTAGICE3 100-mil adapter cannot be used with the SAM connector port, since pins 2 and 10
(AVR GND) on the adapter are connected.
Connection to a custom 100-mil header
If your target board does not have a compliant 10-pin JTAG header in 50- or 100-mil, you can map to a custom
pinout using the 10-pin "mini-squid" cable (included in some kits), which gives access to ten individual 100-mil
sockets.
Connection to a 20-pin 100-mil header
Use the adapter board (included in some kits) to connect to targets with a 20-pin 100-mil header.
Table 3-1. Atmel-ICE JTAG Pin Description
Name AVR
port
pin
SAM
port
pin
Description
TCK 1 4 Test Clock (clock signal from the Atmel-ICE into the target device).
TMS 5 2 Test Mode Select (control signal from the Atmel-ICE into the target device).
TDI 9 8 Test Data In (data transmitted from the Atmel-ICE into the target device).
TDO 3 6 Test Data Out (data transmitted from the target device into the Atmel-ICE).
nTRST 8 - Test Reset (optional, only on some AVR devices). Used to reset the JTAG
TAP controller.
nSRST 6 10 Reset (optional) Used to reset the target device. Connecting this pin is
recommended since it allows the Atmel-ICE to hold the target device in a
reset state, which can be essential to debugging in certain scenarios.
VTG 4 1 Target voltage reference. The Atmel-ICE samples the target voltage on this
pin in order to power the level converters correctly. The Atmel-ICE draws
less than 3mA from this pin in debugWIRE mode and less than 1mA in other
modes.
GND 2, 10 3, 5, 9 Ground. All must be connected to ensure that the Atmel-ICE and the target
device share the same ground reference.
3.3 Connecting to an aWire Target
The aWire interface only requires one data line in addition to Vcc and GND. On the target this line is the
nRESET line, although the debugger uses the JTAG TDO line as the data line.
The recommended pinout for the 6-pin aWire connector is shown in Figure 4-5, “aWire Header
Pinout” on page 22.
Connection to a 6-pin 100-mil aWire header
Use the 6-pin 100-mil tap on the flat cable (included in some kits) to connect to a standard 100-mil aWire
header.
Connection to a 6-pin 50-mil aWire header
Use the adapter board (included in some kits) to connect to a standard 50-mil aWire header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR connector port and the
target board. Three connections are required, as described in the table below.
Table 3-2. Atmel-ICE aWire Pin Mapping
Atmel-ICE AVR port
pins
Target pins Mini-squid pin aWire pinout
Pin 1 (TCK) 1
Pin 2 (GND) GND 2 6

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Atmel-ICE AVR port
pins
Target pins Mini-squid pin aWire pinout
Pin 3 (TDO) DATA 3 1
Pin 4 (VTG) VTG 4 2
Pin 5 (TMS) 5
Pin 6 (nSRST) 6
Pin 7 (Not connected) 7
Pin 8 (nTRST) 8
Pin 9 (TDI) 9
Pin 10 (GND) 0
3.4 Connecting to a PDI Target
The recommended pinout for the 6-pin PDI connector is shown in Figure 4-6, “PDI Header
Pinout” on page 22.
Connection to a 6-pin 100-mil PDI header
Use the 6-pin 100-mil tap on the flat cable (included in some kits) to connect to a standard 100-mil PDI header.
Connection to a 6-pin 50-mil PDI header
Use the adapter board (included in some kits) to connect to a standard 50-mil PDI header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR connector port and the
target board. Four connections are required, as described in the table below.
Note There is a difference from the JTAGICE mkII JTAG probe, where PDI_DATA is connected to pin 9.
The Atmel-ICE is compatible with the pinout used by the JTAGICE3, AVR ONE! and AVR Dragon
products.
Table 3-3. Atmel-ICE PDI Pin Mapping
Atmel-ICE AVR port
pin
Target pins Mini-squid pin Atmel STK600 PDI
pinout
Pin 1 (TCK) 1
Pin 2 (GND) GND 2 6
Pin 3 (TDO) PDI_DATA 3 1
Pin 4 (VTG) VTG 4 2
Pin 5 (TMS) 5
Pin 6 (nSRST) PDI_CLK 6 5
Pin 7 (Not connected) 7
Pin 8 (nTRST) 8
Pin 9 (TDI) 9
Pin 10 (GND) 0
3.5 Connecting to a debugWIRE Target
The recommended pinout for the 6-pin debugWIRE (SPI) connector is shown in Figure 4-7, “debugWIRE (SPI)
Header Pinout” on page 22.
Connection to a 6-pin 100-mil SPI header
Use the 6-pin 100-mil tap on the flat cable (included in some kits) to connect to a standard 100-mil SPI header.

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Connection to a 6-pin 50-mil SPI header
Use the adapter board (included in some kits) to connect to a standard 50-mil SPI header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR connector port and
the target board. Three connections are required, as described in Table 3-4, “Atmel-ICE debugWIRE Pin
Mapping” on page 16.
Although the debugWIRE interface only requires one signal line (RESET), Vcc and GND to operate correctly,
it is advised to have access to the full SPI connector so that the debugWIRE interface can be enabled and
disabled using SPI programming.
When the DWEN fuse is enabled the SPI interface is overridden internally in order for the OCD module to have
control over the RESET pin. The debugWIRE OCD is capable of disabling itself temporarily (using the button
on the debugging tab in the properties dialog in Atmel Studio), thus releasing control of the RESET line. The
SPI interface is then available again (only if the SPIEN fuse is programmed), allowing the DWEN fuse to be
un-programmed using the SPI interface. If power is toggled before the DWEN fuse is un-programmed, the
debugWIRE module will again take control of the RESET pin.
Note It is highly advised to simply let Atmel Studio handle setting and clearing of the DWEN fuse.
It is not possible to use the debugWIRE interface if the lockbits on the target AVR device are programmed.
Always be sure that the lockbits are cleared before programming the DWEN fuse and never set the lockbits
while the DWEN fuse is programmed. If both the debugWIRE enable fuse (DWEN) and lockbits are set,
one can use High Voltage Programming to do a chip erase, and thus clear the lockbits. When the lockbits
are cleared the debugWIRE interface will be re-enabled. The SPI Interface is only capable of reading fuses,
reading signature and performing a chip erase when the DWEN fuse is un-programmed.
Table 3-4. Atmel-ICE debugWIRE Pin Mapping
Atmel-ICE AVR port pin Target pins Mini-squid pin
Pin 1 (TCK) 1
Pin 2 (GND) GND 2
Pin 3 (TDO) 3
Pin 4 (VTG) VTG 4
Pin 5 (TMS) 5
Pin 6 (nSRST) RESET 6
Pin 7 (Not connected) 7
Pin 8 (nTRST) 8
Pin 9 (TDI) 9
Pin 10 (GND) 0
3.6 Connecting to a SPI Target
The recommended pinout for the 6-pin SPI connector is shown in Figure 4-8, “SPI Header
Pinout” on page 23.
Connection to a 6-pin 100-mil SPI header
Use the 6-pin 100-mil tap on the flat cable (included in some kits) to connect to a standard 100-mil SPI header.
Connection to a 6-pin 50-mil SPI header
Use the adapter board (included in some kits) to connect to a standard 50-mil SPI header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR connector port and the
target board. Six connections are required, as described in the table below.

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Note The SPI interface is effectively disabled when the debugWIRE enable fuse (DWEN) is
programmed, even if SPIEN fuse is also programmed. To re-enable the SPI interface, the 'disable
debugWIRE' command must be issued while in a debugWIRE debugging session. Disabling
debugWIRE in this manner requires that the SPIEN fuse is already programmed. If Atmel Studio
fails to disable debugWIRE, it is probable that the SPIEN fuse is NOT programmed. If this is the
case, it is necessary to use a high-voltage programming interface to program the SPIEN fuse.
Table 3-5. Atmel-ICE SPI Pin Mapping
Atmel-ICE AVR port
pins
Target pins Mini-squid pin SPI pinout
Pin 1 (TCK) SCK 1 3
Pin 2 (GND) GND 2 6
Pin 3 (TDO) MISO 3 1
Pin 4 (VTG) VTG 4 2
Pin 5 (TMS) 5
Pin 6 (nSRST) /RESET 6 5
Pin 7 (Not connected) 7
Pin 8 (nTRST) 8
Pin 9 (TDI) MOSI 9 4
Pin 10 (GND) 0
3.7 Connecting to a TPI Target
The recommended pinout for the 6-pin TPI connector is shown in Figure 4-9, “TPI Header
Pinout” on page 23.
Connection to a 6-pin 100-mil TPI header
Use the 6-pin 100-mil tap on the flat cable (included in some kits) to connect to a standard 100-mil TPI header.
Connection to a 6-pin 50-mil TPI header
Use the adapter board (included in some kits) to connect to a standard 50-mil TPI header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR connector port
and the target board. Six connections are required, as described in Table 3-6, “Atmel-ICE TPI Pin
Mapping” on page 17.
Table 3-6. Atmel-ICE TPI Pin Mapping
Atmel-ICE AVR port
pins
Target pins Mini-squid pin TPI pinout
Pin 1 (TCK) CLOCK 1 3
Pin 2 (GND) GND 2 6
Pin 3 (TDO) DATA 3 1
Pin 4 (VTG) VTG 4 2
Pin 5 (TMS) 5
Pin 6 (nSRST) /RESET 6 5
Pin 7 (Not connected) 7
Pin 8 (nTRST) 8
Pin 9 (TDI) 9
Pin 10 (GND) 0
3.8 Connecting to a SWD Target

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The ARM SWD interface is s subset of the JTAG interface, making use of TCK and TMS pins, which means
that when connecting to an SWD device, the 10-pin JTAG connector can technically be used. The ARM JTAG
and AVR JTAG connectors are however not pin-compatible, so this depends upon the layout of the target board
in use. When using STK600 or a board making use of the AVR JTAG pinout, the AVR connector port on the
Atmel-ICE must be used. When connecting to a board which makes use of the ARM JTAG pinout, the SAM
connector port on the Atmel-ICE must be used.
The recommended pinout for the 10-pin Cortex Debug connector is shown in Figure 4-10, “Recommended
ARM SWD/JTAG Header Pinout” on page 23.
Connection to a 10-pin 50-mil Cortex header
Use the flat cable (included in some kits) to connect to a standard 50-mil Cortex header.
Connection to a 10-pin 100-mil Cortex-layout header
Use the adapter board (included in some kits) to connect to a 100-mil Cortex-pinout header.
Connection to a 20-pin 100-mil SAM header
Use the adapter board (included in some kits) to connect to a 20-pin 100-mil SAM header.
Connection to a custom 100-mil header
The 10-pin mini-squid cable should be used to connect between the Atmel-ICE AVR or SAM connector port
and the target board. Six connections are required, as described in the table below.
Table 3-7. Atmel-ICE SWD Pin Mapping
Name AVR
port
pin
SAM
port
pin
Description
SWDCLK 1 4 Serial Wire Debug Clock.
SWDIO 5 2 Serial Wire Debug Data Input/Output.
SWO 3 6 Serial Wire Output (optional- not implemented on all devices).
nSRST 6 10 Reset.
VTG 4 1 Target voltage reference.
GND 2, 10 3, 5 Ground.

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4. On-Chip Debugging
4.1 Introduction to On-Chip Debugging (OCD)
A traditional Emulator is a tool which tries to imitate the exact behaviour of a target device. The closer this
behaviour is to the actual device’s behaviour, the better the emulation will be.
The Atmel-ICE is not a traditional Emulator. Instead, the Atmel-ICE interfaces with the internal On-Chip Debug
system inside the target device, providing a mechanism for monitoring and controlling its execution. In this way
the application being debugged is not emulated, but actually executed on the real target device.
With an OCD system, the application can be executed whilst maintaining exact electrical and timing
characteristics in the target system – something not technically realisable with a traditional emulator.
Run Mode
When in Run mode, the execution of code is completely independent of the Atmel-ICE. The Atmel-ICE will
continuously monitor the target device to see if a break condition has occurred. When this happens the OCD
system will interrogate the device through its debug interface, allowing the user to view the internal state of the
device.
Stopped Mode
When a breakpoint is reached, program execution is halted, but all I/O will continue to run as if no breakpoint
had occurred. For example assume that a USART transmit has just been initiated when a breakpoint is
reached. In this case the USART continues to run at full speed completing the transmission, even though the
core is in stopped mode.
Hardware Breakpoints
The target OCD module contains a number of program counter comparators implemented in hardware. When
the program counter matches the value stored in one of the comparator registers, the OCD enters stopped
mode. Since hardware breakpoints require dedicated hardware on the OCD module, the number of breakpoints
available depends upon the size of the OCD module implemented on the target. Usually one such hardware
comparator is ‘reserved’ by the debugger for internal use. For more information on the hardware breakpoints
available in the various OCD modules, see “Atmel OCD Implementations” on page 23 .
Software Breakpoints
A software breakpoint is a BREAK instruction placed in program memory on the target device. When this
instruction is loaded, program execution will break and the OCD enters stopped mode. To continue execution
a "start" command has to be given from the OCD. Not all AVR devices have OCD modules supporting the
BREAK instruction. For more information on the software breakpoints available in the various OCD modules,
see “Atmel OCD Implementations” on page 23.
For further information on the considerations and restrictions when using an OCD system, see “Special
Considerations” on page 32.
4.2 Physical Interfaces
The Atmel-ICE supports several hardware interfaces as described in the following sections.
4.2.1 JTAG
The JTAG interface consists of a 4-wire Test Access Port (TAP) controller that is compliant with the IEEE
1149.1 standard. The IEEE standard was developed to provide an industry-standard way to efficiently test
circuit board connectivity (Boundary Scan). Atmel AVR and SAM devices have extended this functionality to
include full Programming and On-Chip Debugging support.
Figure 4-1. JTAG Interface Basics
Atmel
target device
Atmel-ICE
Vcc
TMS
TDI
TDO
TCK

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When designing an application PCB which includes an Atmel AVR with the JTAG interface, it is recommended
to use the pinout as shown in Figure 4-2, “AVR JTAG Header Pinout” on page 20. The Atmel-ICE can
connect to both 100-mil and 50-mil variants of this pinout.
Figure 4-2. AVR JTAG Header Pinout
GND
VCC
/RESET
(TRST)
GND
TCK
TDO
TMS
TDI
1 2
AVR JTAG
(NC)
Table 4-1. AVR JTAG Pin Description
Name Pin Description
TCK 1 Test Clock (clock signal from the Atmel-ICE into the target device).
TMS 5 Test Mode Select (control signal from the Atmel-ICE into the target device).
TDI 9 Test Data In (data transmitted from the Atmel-ICE into the target device).
TDO 3 Test Data Out (data transmitted from the target device into the Atmel-ICE).
nTRST 8 Test Reset (optional, only on some AVR devices). Used to reset the JTAG TAP
controller.
nSRST 6 Reset (optional) Used to reset the target device. Connecting this pin is recommended
since it allows the Atmel-ICE to hold the target device in a reset state, which can be
essential to debugging in certain scenarios.
VTG 4 Target voltage reference. The Atmel-ICE samples the target voltage on this pin in
order to power the level converters correctly. The Atmel-ICE draws less than 3mA
from this pin in debugWIRE mode and less than 1mA in other modes.
GND 2, 10 Ground. Both must be connected to ensure that the Atmel-ICE and the target device
share the same ground reference.
Tip Remember to include a decoupling capacitor between pin 4 and GND.
When designing an application PCB which includes an Atmel SAM with the JTAG interface, it is recommended
to use the pinout as shown in Figure 4-3, “SAM JTAG Header Pinout” on page 20. The Atmel-ICE can
connect to both 100-mil and 50-mil variants of this pinout.
Figure 4-3. SAM JTAG Header Pinout
TMS
TCK
TDO
TDI
nRESET
VCC
GND
GND
(KEY)
GND
1 2
SAM JTAG
Table 4-2. SAM JTAG pin description
Name Pin Description
TCK 4 Test Clock (clock signal from the Atmel-ICE into the target device).
TMS 3 Test Mode Select (control signal from the Atmel-ICE into the target device).
TDI 8 Test Data In (data transmitted from the Atmel-ICE into the target device).
TDO 6 Test Data Out (data transmitted from the target device into the Atmel-ICE).
nRESET 10 Reset (optional) Used to reset the target device. Connecting this pin is recommended
since it allows the Atmel-ICE to hold the target device in a reset state, which can be
essential to debugging in certain scenarios.