night_mare
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« on: April 11, 2010, 04:29:46 16:29 » |
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Is it possible to change BAUD Rate from 36000 b/s to 9600 b/s by using any software or circuit??
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zawmintun1
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« Reply #1 on: April 12, 2010, 03:49:45 15:49 » |
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Hello night_mare I think it can finish using PIC such as PIC16F628A. RS232 Data is saved in PIC & you can change BAUD by firmware then go out But it a not good Idea because data loss in a time if you use in GPS Data Sorry for my Bad English Good Luck
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DreamCat
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« Reply #2 on: April 12, 2010, 05:40:10 17:40 » |
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maybe you want do the baudrate conveter. if it is, FriskyFerret said is right. you need a buffer, but, if baudrate from high to low convert, and no pause, it is impossible to achieve, data will be lost.
only if your data not continuous, you can use software or hardware do this. for mcu, you can chose the two uart built-in type, or one uart built-in type and use software implement another uart.
----------------------------- Another consideration, if you want change baudrate on device running, many device need you send a command tell them you need change speed. such as power meter, cdma or the other....
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May be I expressed the wrong meaning, sorry for my bad english. Please correct it for me if you can.
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night_mare
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« Reply #3 on: April 14, 2010, 02:57:56 14:57 » |
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i think infinite buffer is impossible.......... Dreamcat, actually i m working on a radar. I need to change its baud rate to fed it plotting table. And i am really frustated about this project...........
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twonuts
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« Reply #4 on: April 14, 2010, 04:25:13 16:25 » |
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If your data is numerical, you might try averaging a 4 byte data in sequence, then send single averaged byte to your plot table. That way you get a 4:1 ratio of data in:out. No bytes are missed. You can still use limited buffering of input data.
You might need to modify the ratio slightly for better accuracy of averaging, and matching of baud rates. 36k/9k6 isn't quite 4:1, but gives this you an idea the general method.
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« Last Edit: April 14, 2010, 04:28:34 16:28 by twonuts »
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DreamCat
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« Reply #5 on: April 14, 2010, 04:59:56 16:59 » |
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dose your radar device supports multi-rate? if not supports, I think you can receive the data comes from radar first, and do the data process. at the end send it out on 9600bps.
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May be I expressed the wrong meaning, sorry for my bad english. Please correct it for me if you can.
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night_mare
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« Reply #6 on: April 15, 2010, 01:09:30 01:09 » |
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twonuts could u plz tell details..........
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FriskyFerret
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Put it in, take it out.
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« Reply #7 on: April 15, 2010, 03:29:23 15:29 » |
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What kind of radar?
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Dancing pants and leotards, that's what I'm talkin' about!
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oldboy
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« Reply #8 on: September 27, 2010, 06:09:53 06:09 » |
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Not sure if you have already found a satisfactory answer. If got an invite recently and feel I can provide better information than already posted. Adding to twonuts suggestion: Knowledge of the nature of data would be useful in pointing you to a better direction. Look for information about information coding: e.g. if you have long sequences of ones and zeros, run length coding http://en.wikipedia.org/wiki/Run-length_encodingor for more sequences of repeated data, huffman coding: http://en.wikipedia.org/wiki/Huffman_coding
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