Re: 50 baud is dead
Chuck Robey wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Warren Block wrote: On Sun, 13 Jul 2008, Daniel O'Connor wrote: On Sat, 12 Jul 2008, Christian Weisgerber wrote: Daniel O'Connor [EMAIL PROTECTED] wrote: It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. The data sheet disagrees. The flexible baud rate generator of PL-2303X could be programmed to generate any rate between 75 bps and 6Mbps. I guess you're out of luck then :( Or just try it at 75 and see if there's enough slop to read the 50 baud data. There won't be, 50% is way too far off, I think (from experiments I did 30 years back) that about 12% is the limit, when I had access to the best regenerators. Regens don't even get used anymore. I forget the actual limit I probed, but I know 1/2 over is way too far to go. -Warren Block * Rapid City, South Dakota USA first, in very round numbers, you get about five per cent error in the bit_time for fifty per cent error in ten bits. usually, there are three reads, all near the center of the bit_time. so, ya gotta be kinda close. two per cent leaves plenty of room for slop. i have an inexpensive hardware solution. if any one is interested, please respond off_list, unless you think it appropriate for -chat. rob ___ freebsd-chat@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-chat To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: 50 baud is dead
On Sun, 13 Jul 2008, Daniel O'Connor wrote: On Sat, 12 Jul 2008, Christian Weisgerber wrote: Daniel O'Connor [EMAIL PROTECTED] wrote: It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. The data sheet disagrees. The flexible baud rate generator of PL-2303X could be programmed to generate any rate between 75 bps and 6Mbps. I guess you're out of luck then :( Or just try it at 75 and see if there's enough slop to read the 50 baud data. -Warren Block * Rapid City, South Dakota USA ___ freebsd-chat@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-chat To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: 50 baud is dead
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Warren Block wrote: On Sun, 13 Jul 2008, Daniel O'Connor wrote: On Sat, 12 Jul 2008, Christian Weisgerber wrote: Daniel O'Connor [EMAIL PROTECTED] wrote: It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. The data sheet disagrees. The flexible baud rate generator of PL-2303X could be programmed to generate any rate between 75 bps and 6Mbps. I guess you're out of luck then :( Or just try it at 75 and see if there's enough slop to read the 50 baud data. There won't be, 50% is way too far off, I think (from experiments I did 30 years back) that about 12% is the limit, when I had access to the best regenerators. Regens don't even get used anymore. I forget the actual limit I probed, but I know 1/2 over is way too far to go. -Warren Block * Rapid City, South Dakota USA ___ freebsd-chat@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-chat To unsubscribe, send any mail to [EMAIL PROTECTED] -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.9 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkh6MrsACgkQz62J6PPcoOmBrwCfRIbcU4yoZrApBR32AYdFBqtn t6wAn1yw4mK9WE0jxjEu7/XTI1iG/y3N =mZOo -END PGP SIGNATURE- ___ freebsd-chat@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-chat To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: 50 baud is dead
Daniel O'Connor [EMAIL PROTECTED] wrote: It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. The data sheet disagrees. The flexible baud rate generator of PL-2303X could be programmed to generate any rate between 75 bps and 6Mbps. -- Christian naddy Weisgerber [EMAIL PROTECTED] ___ freebsd-chat@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-chat To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: 50 baud is dead
On Sat, 12 Jul 2008, Christian Weisgerber wrote: Daniel O'Connor [EMAIL PROTECTED] wrote: It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. The data sheet disagrees. The flexible baud rate generator of PL-2303X could be programmed to generate any rate between 75 bps and 6Mbps. I guess you're out of luck then :( It would be pretty straightforward to get a microcontroller to interface to it instead (eg dual UART) Hmm, I wonder if you can oversample and use a higher baud rate (obviously would require modified ntpd) -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au The nice thing about standards is that there are so many of them to choose from. -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C signature.asc Description: This is a digitally signed message part.
Re: 50 baud is dead
On Sat, 12 Jul 2008, Christian Weisgerber wrote: Today I thought I'd hook up a simple DCF77 radio clock receiver, serial port type, by way of a USB-to-serial converter. Just to see how this compares to the same gadget hooked up to an actual serial port (which are getting rare). ntpd[37130]: ntpd 4.2.0-a Sun Jul 6 13:31:43 CEST 2008 (1) ntpd[37130]: PARSE receiver #1: parse_start: tcsetattr(14, tio): Input/output error ntpd[37130]: internal error: refclockio structure not found It turns out that uplcom(4) adapters don't support the required speed of 50 baud anymore. The times they are a-changin'. [Please note that I have posted this as a curious observation; it is not a request for assistance.] You know, it might actually support it if you hack up the driver. The source says the PL2303X can set any rate. Worth a try anyway :) -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au The nice thing about standards is that there are so many of them to choose from. -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C signature.asc Description: This is a digitally signed message part.
