Emulating ATmega103/603
2-2 AVR
®
ATICE30 User Guide
2.2 Configuration of
the ATmegaPOD
2.2.1 Voltage Regulation
for Port Pins
If the target system uses its own power supply, the output voltage must be set to the
voltage in the target system. The jumpers J200 - J202 are used for this purpose. The
interpretation of the different settings of these jumpers is shown in Figure 2-2.
Figure 2-2. Jumper Settings
2.2.2 Power to Target PCB The ATmegaICE can power the target PCB with 5.0V. To enable this option, J500
should be mounted. Note that the absolute maximum supply current is 1.0A, so the tar-
get should use less than 5W of power to use this option. Jumpers J200 - J202 must all
be removed when external power is selected. If the target application uses voltages
other than 5.0V, it must supply its own power and J500 must be removed.
2.2.3 Clock Setting The external clock system can be set to use either an external crystal or an external
clock signal. To use an external crystal, select External Oscillator in the Emulator
Options menu in AVR Studio, and select an appropriate frequency range for the
mounted crystal. It is important to tune the oscillator driver by choosing the range in the
Clock Range menu to make the clock system work properly with an external crystal.
J300 must be open when using an external crystal. If an external clock signal is used
(on pin XTAL1), jumper J300 must be mounted. This setting also requires the user to
select External Oscillator in the Emulator Options menu in AVR Studio.
ATmegaICE also has a very accurate programmable internal clock that can be used for
emulation. Select this clock by choosing Internal Oscillator in the Emulator Options
menu in AVR Studio. The setting of J300 on the ATmegaPOD and crystals and clock
signals in the user application are insignificant when the internal oscillator is selected.
2.2.4 Timer Oscillator
Setting
In order to enable the timer oscillator, jumper J351 must be mounted. When J351 is
mounted, the setting of J350 determines whether to use an external clock signal or the
local oscillator. If J350 is mounted, the external clock signal is used (on pin TOSC1). If
J350 is not mounted, an external crystal is expected to be mounted between the TOSC1
and TOSC2 pins. When an external crystal is used (J350 not mounted), jumpers J352
and J354 should be used to indicate the frequency range of the oscillator. The interpre-
tation of the different settings for these jumpers is given in Figure 2-3.
2,7 - 2,9
3,0 - 3,3
3,4 - 3,7
3,8 - 4,1
4,2 - 4,5
4,6 - 4,8
4,9 - 5,1
5,2 - 5,5
Target V (V) J202 J201 J200
CC
