Emulating ATmega161
3-2 AVR
®
ATICE30 User Guide
3.2 Configuration
of the
AT90ADCPOD
3.2.1 Voltage Regulation
for Port Pins
If the target system uses its own power supply, the jumper named Ext. Power (J102)
must, under all circumstances, be removed and the output voltage must be set to the
voltage in the target system. The jumpers PW0 - PW2 are used for this purpose. The
interpretation of the different settings of these jumpers is shown in Figure 3-2.
Figure 3-2. Jumper Settings
3.2.2 Power to Target PCB The ATmegaICE can power the target application with 5.0V. To enable this option the
jumper named Ext. Power should be mounted. Jumpers PW0 - PW2 must all be
removed when external power is selected. Note that the absolute maximum supply cur-
rent is 1.0A, so the target should use less than 5W of power to use this option. If the
target application uses voltages other than 5.0V, it must supply its own power and J500
must be removed.
3.2.3 Clock Setting AT90ADCPOD can use one of three available clock sources: the programmable internal
clock in the ICE30, a crystal or an external oscillator in the user application.
The internal clock can be selected by choosing Internal Oscillator in the Emulator
Options menu in AVR Studio. The internal clock can be adjusted between 400 kHz and
20 MHz.
To use an external clock source, select External Oscillator in the Emulator Options
menu in AVR Studio. This clock signal can be in the range of 32.768 kHz to 8 MHz. 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. On the pod card, the
XTAL pins are connected to the ICE by using the 2-wire cable. Connect J103 to J306
when emulating ATmega161. Pin 1 on each connector is labeled with *.
If the clock source from the user application is a crystal, connector J101 must be left
open. If the clock source from the user application is an oscillator, a jumper must be
mounted on connector J101. The switch S101 must be in the OFF position in both
cases.
Long leads from your external crystal to the oscillator circuit on the pod may cause prob-
lems. It is possible to mount a crystal in the socket near J103. Do not use the 2-wire
cable if you choose this option. If the crystal is above 1 MHz and this is selected in the
Clock Range menu in Emulator Options in AVR Studio, S101 should be in the ON
position. S101 should be in the OFF position under all other circumstances.
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
PW2 PW1 PW0
Target V (V) (J202) (J201) (J200)
CC
