Re: [time-nuts] Hyperterminal with variable baud rate
A friend of mine had a need for a round 500Kbit baud rate. What he did was use some FDTI USB/RS232 chip. He could patch the timing values for an existing baud rate (300 baud or something else normally not used). I believe in the Windows registry. This way the (terminal) software can select the patched baud rate and it will in effect behave as the custom baud rate. Cheers, Joop ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
On 11/18/2010 2:32 PM, Elio Corbolante wrote: From: Hal Murray hmur...@megapathdsl.net Are there any terminal programs out there that allow you to select rates other than the standard values? You can use the wonderful Tera Term (http://ttssh2.sourceforge.jp/): it accepts nonstandard values in the speed parameter. I verified it with an oscilloscope. _ Elio. PuTTY has a serial mode that does this as well. As long as the rate is 115200 divided by an integer, it works. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
On Thu, Nov 18, 2010 at 11:55 AM, Corby Dawson cdel...@juno.com wrote: Are there any terminal programs out there that allow you to select rates other than the standard values? https://sites.google.com/site/terminalbpp/ Select 'Custom'. -- http://blog.softwaresafety.net/ http://www.designer-iii.com/ http://www.wearablesmartsensors.com/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
Corby Dawson cdel...@juno.com wrote: At the lower clock rate I can't communicate as the corrected baud rate comes out to 955 baud. [...] Are there any terminal programs out there that allow you to select rates other than the standard values? The restriction to standard baud rates only is a hardware limitation (in the standard UARTs), not a software one. With standard PC UARTs the baud rate can only be 115200/N where N is an integer; with most non-PC UARTs it's often even more restrictive as they use a clock MUX with, say, 16 inputs rather than a divider which you can program like the PC UART. MS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
To possibilities come to mind: An old version (DOS) of ProComm might have the BAUD rate generator constants accessible. Some older RS-232 testers have adjustable (with a pot) BAUD rates. FWIW, -John = Are there any terminal programs out there that allow you to select rates other than the standard values? I doubt if you will have much luck in that area, but please let me/us know if you find something. The API from user code to the kernel for the baud rate is usually pick one from a small set. (At least in Unix/Posix.) I'd like to avoid any hardware kludges and hopefully make the fix in the terminal software. Several ideas... If you are using Linux, you could build your own kernel. Then find the module for your serial chip and patch the baud rate table so that one of the normal speeds you don't use would run at the speed you want. You could also get a PCI card with a serial interface. It will have a crystal on it, probably in an oscillator package. Change that crystal to something that fits your needs. That will scale all of the speeds on that card so it probably won't be useful for anything else. Another approach would be to get a micro with two serial interfaces and write a speed-changing program. Since you are working on the raw hardware, you can set the speeds to whatever you want. I'm picturing 2 buffers (one each direction) and a big loop that: Character ready on line 1: read it and put it in the buffer Character ready on line 2: read it and put it in the other buffer Space available on line 1 and data in buffer? Send a character ... You would need flow control in the fast-slow direction, or set things up so that the buffer is big enough for all the messages you send and your program (or human) waits long-enough between messages. -- These are my opinions, not necessarily my employer's. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
From: Hal Murray hmur...@megapathdsl.net Are there any terminal programs out there that allow you to select rates other than the standard values? I doubt if you will have much luck in that area, but please let me/us know if you find something. You can use the wonderful Tera Term (http://ttssh2.sourceforge.jp/): it accepts nonstandard values in the speed parameter. I verified it with an oscilloscope. _ Elio. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
How far are you from a settable rate?The whole beauty of asynchronous serial is that you can tolerate huge (5-10%) errors in timing On Nov 18, 2010, at 10:37 AM, Hal Murray hmur...@megapathdsl.net wrote: Are there any terminal programs out there that allow you to select rates other than the standard values? I doubt if you will have much luck in that area, but please let me/us know if you find something. The API from user code to the kernel for the baud rate is usually pick one from a small set. (At least in Unix/Posix.) I'd like to avoid any hardware kludges and hopefully make the fix in the terminal software. Several ideas... I ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
jim...@earthlink.net said: How far are you from a settable rate?The whole beauty of asynchronous serial is that you can tolerate huge (5-10%) errors in timing 10% is pushing it. In the simple/common 8N1 case, you have a start bit, 8 data bits, and a stop bit. The nasty case is when all the data bits are the same as the start bit. When you get to the transition for the stop bit, you have to decide if there were 7 or 8 data bits. (Well, the UART has decided already, you just hope it got the right answer.) Don't forget to round up/down by the asymmetry in rise/fall times. If there are transitions within the data byte the receiver can resynchronize. But yes, I agree that the timing can be pretty sloppy. -- These are my opinions, not necessarily my employer's. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Hyperterminal with variable baud rate
Corby, once you have tried this: http://www.docklight.de/index.htm you don't want to use anything else. That comes from the fact that it is not exactly a terminal program instead it is a diagnostic program for problems with serial ports. The free evaluation version lets you do anything with the exception to save some settings. The scroll box for the baud rate lets you edit any baud rate and with non-standard baud rates you get a message about possible errors. Note that the keyboard is not enabled at program start. You have have to klick on the small keyboard icon to enable it. regards Ulrich Bangert -Ursprungliche Nachricht- Von: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] Im Auftrag von Corby Dawson Gesendet: Donnerstag, 18. November 2010 17:55 An: time-nuts@febo.com Betreff: [time-nuts] Hyperterminal with variable baud rate Hi, I am using a module from a rubidium standard to do some experiments. I am using a much lower clock rate into the module which has RS232 comm. At the lower clock rate I can't communicate as the corrected baud rate comes out to 955 baud. I can communicate if I keep the clock rate a binary ratio to the original clock rate albeit at a submultiple of the original 9600 baud. For instance at a clock rate of 6.28Mhz I can talk at 1200 baud, but I want to use 5Mhz as the clock rate. Are there any terminal programs out there that allow you to select rates other than the standard values? I'd like to avoid any hardware kludges and hopefully make the fix in the terminal software. Thanks, Corby Dawson Mortgage Rates Hit 2.67%! If you owe under $729k you probably qualify for Gov't Refi Programs http://thirdpartyoffers.juno.com/TGL3141/4ce55abf5c4b640e9cm04duc ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
