WormFood's AVR Baud Rate Calculator

Brought to you by rue_mohr with permission from Wormfood given "Anything ever happens to me"
Sorry its not a newer version.
Bit Rate Show table of all possible clock speeds, for a given bit rate
Clock Freq, in Mhz Show table of all possible bit rates, for a given clock speed
show additional double speed mode information
show additional synchronous mode information

32.768 Khz
Bit RateUBRR% of error
30062.5
600212.1
1200117.2
2400017.2
48000134.4
96000368.8
144000603.1
192000837.5
2880001306.2
3840001775.0
5760002712.5
7680003650.0
11520005525.0
230400011150.0
1 Mhz
Bit RateUBRR% of error
3002070.2
6001030.2
1200510.2
2400250.2
4800120.2
960067.5
1440037.8
1920027.8
2880017.8
38400122.9
5760007.8
76800022.9
115200084.3
2304000268.6
1.2288 Mhz
Bit RateUBRR% of error
3002550.0
6001270.0
1200630.0
2400310.0
4800150.0
960070.0
1440046.2
1920030.0
28800212.5
3840010.0
57600025.0
7680000.0
115200050.0
2304000200.0
1.8432 Mhz
Bit RateUBRR% of error
3003830.0
6001910.0
1200950.0
2400470.0
4800230.0
9600110.0
1440070.0
1920050.0
2880030.0
3840020.0
5760010.0
76800133.3
11520000.0
2304000100.0
2 Mhz
Bit RateUBRR% of error
3004160.1
6002070.2
12001030.2
2400510.2
4800250.2
9600120.2
1440083.7
1920067.5
2880037.8
3840027.8
5760017.8
76800122.9
11520007.8
230400084.3
2.4576 Mhz
Bit RateUBRR% of error
3005110.0
6002550.0
12001270.0
2400630.0
4800310.0
9600150.0
14400103.1
1920070.0
2880046.2
3840030.0
57600212.5
7680010.0
115200025.0
230400050.0
3.2768 Mhz
Bit RateUBRR% of error
3006820.0
6003400.1
12001700.2
2400840.4
4800420.8
9600201.6
14400131.6
19200103.1
2880061.6
3840046.2
57600312.5
76800212.5
115200112.5
230400012.5
3.579545 Mhz
Bit RateUBRR% of error
3007450.0
6003720.0
12001850.2
2400920.2
4800460.8
9600221.3
14400153.0
19200113.0
2880073.0
3840053.0
5760033.0
7680023.0
11520013.0
23040003.0
3.6864 Mhz
Bit RateUBRR% of error
3007670.0
6003830.0
12001910.0
2400950.0
4800470.0
9600230.0
14400150.0
19200110.0
2880070.0
3840050.0
5760030.0
7680020.0
11520010.0
23040000.0
4 Mhz
Bit RateUBRR% of error
3008320.0
6004160.1
12002070.2
24001030.2
4800510.2
9600250.2
14400162.1
19200120.2
2880083.7
3840067.5
5760037.8
7680027.8
11520017.8
23040007.8
4.194304 Mhz
Bit RateUBRR% of error
3008730.0
6004360.0
12002170.2
24001080.2
4800540.7
9600261.1
14400171.1
19200132.5
2880081.1
3840062.5
5760049.9
76800212.1
115200112.1
230400012.1
4.433619 Mhz
Bit RateUBRR% of error
3009230.0
6004610.0
12002300.0
24001140.4
4800570.5
9600280.5
14400181.3
19200133.0
2880093.9
3840063.0
5760043.9
76800310.9
115200116.9
230400016.9
4.608 Mhz
Bit RateUBRR% of error
3009590.0
6004790.0
12002390.0
24001190.0
4800590.0
9600290.0
14400190.0
19200140.0
2880090.0
3840076.7
5760040.0
7680036.7
115200220.0
230400020.0
4.9152 Mhz
Bit RateUBRR% of error
30010230.0
6005110.0
12002550.0
24001270.0
4800630.0
9600310.0
14400201.6
19200150.0
28800103.1
3840070.0
5760046.2
7680030.0
115200212.5
230400025.0
5 Mhz
Bit RateUBRR% of error
30010410.0
6005200.0
12002590.2
24001290.2
4800640.2
9600321.4
14400211.4
19200151.7
28800101.4
3840071.7
5760047.8
7680031.7
115200210.6
230400026.3
5.0688 Mhz
Bit RateUBRR% of error
30010550.0
6005270.0
12002630.0
24001310.0
4800650.0
9600320.0
14400210.0
19200163.0
28800100.0
3840073.0
5760059.1
7680033.0
11520029.1
230400027.3
6 Mhz
Bit RateUBRR% of error
30012490.0
6006240.0
12003120.2
24001550.2
4800770.2
9600380.2
14400250.2
19200192.4
28800120.2
3840092.4
5760067.5
7680042.4
11520027.8
230400122.9
6.144 Mhz
Bit RateUBRR% of error
30012790.0
6006390.0
12003190.0
24001590.0
4800790.0
9600390.0
14400261.2
19200190.0
28800122.5
3840090.0
5760065.0
7680040.0
115200210.0
230400120.0
7.3728 Mhz
Bit RateUBRR% of error
30015350.0
6007670.0
12003830.0
24001910.0
4800950.0
9600470.0
14400310.0
19200230.0
28800150.0
38400110.0
5760070.0
7680050.0
11520030.0
23040010.0
8 Mhz
Bit RateUBRR% of error
30016660.0
6008320.0
12004160.1
24002070.2
48001030.2
9600510.2
14400340.8
19200250.2
28800162.1
38400120.2
5760083.7
7680067.5
11520037.8
23040017.8
9 Mhz
Bit RateUBRR% of error
30018740.0
6009370.1
12004680.1
24002330.2
48001160.2
9600580.7
14400380.2
19200281.0
28800192.4
38400142.4
5760092.4
7680064.4
11520042.4
230400118.1
9.216 Mhz
Bit RateUBRR% of error
30019190.0
6009590.0
12004790.0
24002390.0
48001190.0
9600590.0
14400390.0
19200290.0
28800190.0
38400140.0
5760090.0
7680076.7
11520040.0
230400220.0
10 Mhz
Bit RateUBRR% of error
30020820.0
60010410.0
12005200.0
24002590.2
48001290.2
9600640.2
14400420.9
19200321.4
28800211.4
38400151.7
57600101.4
7680071.7
11520047.8
230400210.6
11.0592 Mhz
Bit RateUBRR% of error
30023030.0
60011510.0
12005750.0
24002870.0
48001430.0
9600710.0
14400470.0
19200350.0
28800230.0
38400170.0
57600110.0
7680080.0
11520050.0
23040020.0
12 Mhz
Bit RateUBRR% of error
30024990.0
60012490.0
12006240.0
24003120.2
48001550.2
9600770.2
14400510.2
19200380.2
28800250.2
38400192.4
57600120.2
7680092.4
11520067.5
23040027.8
12.288 Mhz
Bit RateUBRR% of error
30025590.0
60012790.0
12006390.0
24003190.0
48001590.0
9600790.0
14400520.6
19200390.0
28800261.2
38400190.0
57600122.5
7680090.0
11520065.0
230400210.0
14.318181 Mhz
Bit RateUBRR% of error
30029820.0
60014900.0
12007450.0
24003720.0
48001850.2
9600920.2
14400610.2
19200460.8
28800300.2
38400221.3
57600153.0
76800113.0
11520073.0
23040033.0
14.746 Mhz
Bit RateUBRR% of error
30030710.0
60015350.0
12007670.0
24003830.0
48001910.0
9600950.0
14400630.0
19200470.0
28800310.0
38400230.0
57600150.0
76800110.0
11520070.0
23040030.0
16 Mhz
Bit RateUBRR% of error
30033320.0
60016660.0
12008320.0
24004160.1
48002070.2
96001030.2
14400680.6
19200510.2
28800340.8
38400250.2
57600162.1
76800120.2
11520083.7
23040037.8
18 Mhz
Bit RateUBRR% of error
30037490.0
60018740.0
12009370.1
24004680.1
48002330.2
96001160.2
14400770.2
19200580.7
28800380.2
38400281.0
57600192.4
76800142.4
11520092.4
23040042.4
18.432 Mhz
Bit RateUBRR% of error
30038390.0
60019190.0
12009590.0
24004790.0
48002390.0
96001190.0
14400790.0
19200590.0
28800390.0
38400290.0
57600190.0
76800140.0
11520090.0
23040040.0
20 Mhz
Bit RateUBRR% of error
30041660.0
60020820.0
120010410.0
24005200.0
48002590.2
96001290.2
14400860.2
19200640.2
28800420.9
38400321.4
57600211.4
76800151.7
115200101.4
23040047.8
30 Mhz
Bit RateUBRR% of error
30062490.0
60031240.0
120015620.0
24007800.0
48003900.1
96001940.2
144001290.2
19200970.4
28800640.2
38400480.4
57600321.4
76800231.7
115200151.7
23040071.7
32.768 Mhz
Bit RateUBRR% of error
30068260.0
60034120.0
120017060.0
24008520.0
48004260.1
96002120.2
144001410.2
192001060.3
28800700.2
38400520.6
57600351.2
76800261.2
115200171.2
23040081.2
40 Mhz
Bit RateUBRR% of error
30083320.0
60041660.0
120020820.0
240010410.0
48005200.0
96002590.2
144001730.2
192001290.2
28800860.2
38400640.2
57600420.9
76800321.4
115200211.4
230400101.4
Legend:
UBRR out of range
UBRR and clock speed are a perfect match
UBRR and clock speed are less than 1% off
UBRR and clock speed are between 1% and 2% off
UBRR and clock speed are between 2% and 3% off
UBRR and clock speed are between 3% and 10% off
UBRR and clock speed is over 10% off


I call this a "baud rate calculator", however, "baud rate" is technically an incorrect term. It should be called a "bit rate calculator". Because people misuse the term "baud" so frequently, many do not know there is a difference between "bit rate" and "baud rate". I use the term "baud rate" on the title, knowing it is wrong, so people would be able to find this page, when searching the web, however, all other references are as "bit rate".

NOTE: This page was originally written when there was only one UBRR register, but newer AVR models have 2 UBRR registers, so some of the lower values that show out of range, are really in range. I will update this page some time in the future.

How to use this page:
Without entering anything, you can get a list of the UBRR settings for many popular clock speeds, and serial port bit rates. What makes this program special, is the fact that you can tell it what serial port bit rate you want, and it will tell you all the possible clock speeds that will generate your desired serial port bit rate. You can also give it a clock speed, and it will tell you all the possible serial port bit rates that can be producted with that clock speed. This is very handy when you are searching through your "junk pile", looking for the right crystal, or oscillator to generate a given serial port bit rate.
If you enter a serial port bit rate, not already listed, then the serial port bit rate will be listed as the last entry on each clock speed table. If you enter a clock speed that is not already listed, then a new clock speed table will be added to the end of the list.

If you would like to contact me about this program, if you have any questions or requests then stop by channel #avr on the FreeNode IRC network.

AVRBaudCalc is ©2005-2011 by WormFood