Atmel STK526, Руководство пользователя, Страница: 23 / 38

Using the STK526
STK526 rev. B Hardware User Guide 2-23
7709B–AVR–05/07
Figure 2-21 . STK526 Configuration for Parallel Programming
Parallel Programming allows any operation on the device. This mode is very usefull if a
crucial fuse has been erased inadvertently. For example, if user disables the SPIEN
fuse from ISP mode, it can only be restored using Parallel Programming.
2.9 Debugging
2.9.1 Debugging with AVR JTAG ICE mkII
Every STK526 can be used for debugging with JTAG ICE MK II using the debugWire
protocol through the ISP connector.
Connect the JTAG ICE mkII as shown in Figure 2-19 (like a simple programming
operation), for debugging help, please refer to AVR Studio® Help information.
When using JTAG ICE MK II for debugging, and as AT90USB82/162 parts are factory
configured with the higher security level set, a chip erase operation will be performed on
the part before debugging. Thus the on-chip flash bootloader will be erased. It can be
restored after the debug session using the bootloader hex file available from ATMEL
website.
Note: Starting a debugWire session will enable the DWEN fuse and disable the SPIEN fuse,
that will prevent ISP programming. AVR Studio® can restore the SPIEN fuse before clos-
ing a debugWire session. However the fuse bits can also be restored in Parallel
Programming mode.
2.10 Test Points
There are 7 test points implemented, these test points are referred in the full schematics
section.
Config.
Pads
Reference
Related Signals Function
TP1 D+ USB D+ data line