atmega3250v-8auatmega325v-8ai ATMEL Corporation, atmega3250v-8auatmega325v-8ai Datasheet - Page 235

• Manufacturer Part Number: atmega3250v-8auatmega325v-8ai
• Description: Atmega3250 8-bit Microcontroller With In-system Programmable Flash
• Manufacturer: ATMEL Corporation

2570L–AVR–08/07
As an example, consider the task of verifying a 1.5V ± 5% input signal at ADC channel 3 when
the power supply is 5.0V and AREF is externally connected to V
The recommended values from
rithm in
“Actions” describes what JTAG instruction to be used before filling the Boundary-scan Register
with the succeeding columns. The verification should be done on the data scanned out when
scanning in the data on the same row in the table.
Table 25-6.
Using this algorithm, the timing constraint on the HOLD signal constrains the TCK clock fre-
quency. As the algorithm keeps HOLD high for five steps, the TCK clock frequency has to be at
least five times the number of scan bits divided by the maximum hold time, t
Step
1
2
3
4
5
6
7
8
9
10
11
Table
Actions
SAMPLE_
PRELOAD
EXTEST
Verify the
COMP bit
scanned
out to be 0
Verify the
COMP bit
scanned
out to be 1
25-6. Only the DAC and port pin values of the Scan Chain are shown. The column
Algorithm for Using the ADC
The lower limit is:
The upper limit is:
ADCEN
1
1
1
1
1
1
1
1
1
1
1
DAC
0x200
0x200
0x200
0x123
0x123
0x200
0x200
0x200
0x143
0x143
0x200
Table 25-5
1024 1,5V 0,95 5V
MUXEN
1024 1,5V 1,05 5V
0x08
0x08
0x08
0x08
0x08
0x08
0x08
0x08
0x08
0x08
0x08
⋅
⋅
are used unless other values are given in the algo-
ATmega325/3250/645/6450
HOLD
⋅
⋅
1
0
1
1
1
1
0
1
1
1
1
⁄
⁄
PRECH
1
1
1
1
0
1
1
1
1
0
1
=
=
291
323
PA3.
Data
CC
=
=
0
0
0
0
0
0
0
0
0
0
0
.
0x123
0x143
PA3.
Control
0
0
0
0
0
0
0
0
0
0
0
hold,max
PA3.
Pull-
up_
Enable
0
0
0
0
0
0
0
0
0
0
0
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