9.1 Troubleshooting Guide

Problem	Reason	Solution
The main power LED is dark	The power switch is OFF	Turn on the power switch
No power source is connected to STK600	Do one of the following: Connect a USB cable between STK600 and a PC. Make sure the PC is turned on. Connect a DC power cable to STK600. Note: The DC jack must have a center pin with positive polarity.
The pre-programmed example code does not toggle the LEDs	There is no AVR device in the socket	Plug the AVR device into the right socket (see ISP Programming and Parallel High-Voltage Programming)
The LEDs are not connected to the I/O ports	Connect the LEDS header to the PORTD header, and SWITCHES header to PORTB header (see LEDs and Switches)
No target voltage	Ensure that the VTG jumper is mounted and that VTG is set above 1.8V. VTG can be adjusted in the programming dialog of Microchip Studio.
The Flash memory is erased	Reprogram the AVR device
The AVR device cannot be programmed using SPI	The AVR device is inserted with a wrong orientation	Check that the notch on the AVR device socket matches the notch on the AVR device
The ISP/PDI headers are not connected	Connect the 6-pin flexible cable between the two 6-pin ISP/PDI headers
The VTARGET voltage is too low	Check the AVR device data sheet for the minimum operating voltage
The memory lock-bits are programmed	Erase the memory before programming
The SPI enable fuse is unprogrammed	Program the SPIEN fuse by following section Parallel High-Voltage Programming or Serial High-Voltage Programming
Reset disable fuse is set	Check the reset disable fuse
SPI frequency is too high	Check STK600 SPI frequency and make sure it is lower than the target clock divided by 4
CKDIV fuse is set	Reduce ISP programming speed
External pull-up resistor on the Reset line is too low	Ensure that the external pull-up resistor is ≥4.7 kΩ
AREF0 jumper mounted	For some devices, the AREF0 is connected to a pin used for the ISP interface. The AREF0 jumper must, therefore, be removed to do serial programming of these devices. See the ISP Programming section for which routing cards this applies.
The AVR device cannot be programmed using JTAG	The VTARGET voltage is too low	Check the AVR device data sheet for the minimum operating voltage
The JTAG headers are not connected	Connect the 10-pin flexible cable between the two 10-pin JTAG headers. See JTAG Programming.
The JTAG enable fuse is unprogrammed	Program the JTAGEN fuse by following section Parallel High-Voltage Programming or Serial High-Voltage Programming
The memory lock bits are programmed	Erase the memory before programming
The AVR device cannot be programmed using high-voltage programming	The VTARGET voltage is too low	Ensure that the voltage is at least 4.5V
The high-voltage programming headers are not connected	Mount cables between the programming headers. See Parallel High-Voltage Programming or Serial High-Voltage Programming
The reset jumper is not mounted	Mount the reset jumper
The I/O ports are connected to peripheral circuitry (LEDs, switches, etc.)	Remove all peripheral connections from the I/O ports belonging to the high-voltage programming interface
The memory lock-bits are programmed	Erase the memory before programming
AREF0 jumper mounted	For some devices, the AREF0 is connected to a pin used for the parallel programming interface. The AREF0 jumper must, therefore, be removed to do parallel programming of these devices. See the Parallel High-Voltage Programming section for which routing cards this applies.
Microchip Studio cannot connect to STK600	The USB cable is not connected, or the power is off	Connect the USB cable
The firmware is in a hang-up state	Toggle power on STK600
The status LED is blinking orange	A wrong combination of routing and socket card or the card is removed when the kit is powered	Check the device support file for routing and socket card combination. Always turn OFF the kit power before removing or mounting routing and socket cards.
The status LED is blinking orange	The mounted cards are not recognized by STK600	The routing and socket card identification table in STK600 must be upgraded. Start Microchip Studio and connect to the kit using programming dialog. This will initiate a silent upgrade of the routing and socket card table in the STK600 controller.
The status LED is blinking red with low frequency	Short circuit on VTarget or AREF	Resolve the short circuit
The status LED is blinking red with high frequency	Too much current drawn from the power supply	If the kit is powered by USB, try connecting external power to the DC jack
The status LED is steady red	Slave MCU not responding	Force STK600 into Bootloader mode, and perform a firmware upgrade
The LEDs do not work (running from external VTarget)	STK600 must be powered for LEDs to work	Supply power to STK600 and turn it ON

The main power LED is dark

The power switch is OFF

Turn on the power switch

No power source is connected to STK600

Do one of the following:

Connect a USB cable between STK600 and a PC. Make sure the PC is turned on.
Connect a DC power cable to STK600. Note: The DC jack must have a center pin with positive polarity.

The pre-programmed example code does not toggle the LEDs

There is no AVR device in the socket

Plug the AVR device into the right socket (see ISP Programming and Parallel High-Voltage Programming)

The LEDs are not connected to the I/O ports

Connect the LEDS header to the PORTD header, and SWITCHES header to PORTB header (see LEDs and Switches)

No target voltage

Ensure that the VTG jumper is mounted and that VTG is set above 1.8V. VTG can be adjusted in the programming dialog of Microchip Studio.

The Flash memory is erased

Reprogram the AVR device

The AVR device cannot be programmed using SPI

The AVR device is inserted with a wrong orientation

Check that the notch on the AVR device socket matches the notch on the AVR device

The ISP/PDI headers are not connected

Connect the 6-pin flexible cable between the two 6-pin ISP/PDI headers

The VTARGET voltage is too low

Check the AVR device data sheet for the minimum operating voltage

The memory lock-bits are programmed

Erase the memory before programming

The SPI enable fuse is unprogrammed

Program the SPIEN fuse by following section Parallel High-Voltage Programming or Serial High-Voltage Programming

Reset disable fuse is set

Check the reset disable fuse

SPI frequency is too high

Check STK600 SPI frequency and make sure it is lower than the target clock divided by 4

CKDIV fuse is set

Reduce ISP programming speed

External pull-up resistor on the Reset line is too low

Ensure that the external pull-up resistor is ≥4.7 kΩ

AREF0 jumper mounted

For some devices, the AREF0 is connected to a pin used for the ISP interface. The AREF0 jumper must, therefore, be removed to do serial programming of these devices. See the ISP Programming section for which routing cards this applies.

The AVR device cannot be programmed using JTAG

The VTARGET voltage is too low

Check the AVR device data sheet for the minimum operating voltage

The JTAG headers are not connected

Connect the 10-pin flexible cable between the two 10-pin JTAG headers. See JTAG Programming.

The JTAG enable fuse is unprogrammed

Program the JTAGEN fuse by following section Parallel High-Voltage Programming or Serial High-Voltage Programming

The memory lock bits are programmed

Erase the memory before programming

The AVR device cannot be programmed using high-voltage programming

The VTARGET voltage is too low

Ensure that the voltage is at least 4.5V

The high-voltage programming headers are not connected

Mount cables between the programming headers. See Parallel High-Voltage Programming or Serial High-Voltage Programming

The reset jumper is not mounted

Mount the reset jumper

The I/O ports are connected to peripheral circuitry (LEDs, switches, etc.)

Remove all peripheral connections from the I/O ports belonging to the high-voltage programming interface

The memory lock-bits are programmed

Erase the memory before programming

AREF0 jumper mounted

For some devices, the AREF0 is connected to a pin used for the parallel programming interface. The AREF0 jumper must, therefore, be removed to do parallel programming of these devices. See the Parallel High-Voltage Programming section for which routing cards this applies.

Microchip Studio cannot connect to STK600

The USB cable is not connected, or the power is off

Connect the USB cable

The firmware is in a hang-up state

Toggle power on STK600

The status LED is blinking orange

A wrong combination of routing and socket card or the card is removed when the kit is powered

Check the device support file for routing and socket card combination. Always turn OFF the kit power before removing or mounting routing and socket cards.

The status LED is blinking orange

The mounted cards are not recognized by STK600

The routing and socket card identification table in STK600 must be upgraded. Start Microchip Studio and connect to the kit using programming dialog. This will initiate a silent upgrade of the routing and socket card table in the STK600 controller.

The status LED is blinking red with low frequency

Short circuit on VTarget or AREF

Resolve the short circuit

The status LED is blinking red with high frequency

Too much current drawn from the power supply

If the kit is powered by USB, try connecting external power to the DC jack

The status LED is steady red

Slave MCU not responding

Force STK600 into Bootloader mode, and perform a firmware upgrade

The LEDs do not work (running from external VTarget)

STK600 must be powered for LEDs to work

Supply power to STK600 and turn it ON