ATmega1284 Atmel Corporation, ATmega1284 Datasheet - Page 200

• Manufacturer Part Number: ATmega1284
• Manufacturer: Atmel Corporation

Specifications of ATmega1284

• Flash (kbytes): 128 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Table 19-12. Examples of UBRRn Settings for Commonly Used Oscillator Frequencies (Continued)
1.
8272C–AVR–06/11
Baud
Rate
(bps)
2400
4800
9600
14.4k
19.2k
28.8k
38.4k
57.6k
76.8k
115.2k
230.4k
250k
0.5M
1M
Max.
(1)
UBRR = 0, Error = 0.0%
UBRR
416
207
103
68
51
34
25
16
12
8
3
3
1
0
U2Xn = 0
1Mbps
f
Error
osc
-0.1%
-0.8%
-3.5%
0.2%
0.2%
0.6%
0.2%
0.2%
2.1%
0.2%
8.5%
0.0%
0.0%
0.0%
= 16.0000MHz
UBRR
832
416
207
138
103
68
51
34
25
16
8
7
3
1
U2Xn = 1
2Mbps
Error
-0.1%
-0.1%
-0.8%
-3.5%
0.0%
0.2%
0.2%
0.2%
0.2%
2.1%
0.0%
0.0%
0.0%
0.6%
ATmega164A/PA/324A/PA/644A/PA/1284/P
UBRR
479
239
119
79
59
39
29
19
14
9
4
4
–
–
1.152Mbps
U2Xn = 0
f
Error
osc
-7.8%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
–
–
= 18.4320MHz
UBRR
959
479
239
159
119
59
39
29
19
79
9
8
4
–
2.304Mbps
U2Xn = 1
Error
-7.8%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
2.4%
–
UBRR
520
259
129
86
64
42
32
21
15
10
4
4
–
–
1.25Mbps
U2Xn = 0
f
Error
osc
-0.2%
-1.4%
-1.4%
-1.4%
0.0%
0.2%
0.2%
0.2%
0.9%
1.7%
8.5%
0.0%
–
–
= 20.0000MHz
UBRR
1041
173
129
520
259
86
64
42
32
21
10
9
4
–
U2Xn = 1
2.5Mbps
Error
-0.2%
-1.4%
-1.4%
-1.4%
-0.2%
0.0%
0.0%
0.2%
0.2%
0.2%
0.9%
0.0%
0.0%
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200