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TX <--> TX. Did it again

Started by Tim Wescott June 30, 2015
On 30/06/15 23:17, Tim Wescott wrote:
> Argh. So, I think I manage to get the UART outie hooked up to the USB > and/or RS232 converter outie (and innie to innie) well over half the time. > > And, I just did it again. The STM32F303 has a SWAP bit in its UART > configuration, to swap the TX and RX pins, but that would be cheating > (and besides, I did it with RTS/CTS as well). > > C'mon. Say that _you_ get it right all the time! >
It's a variation of Murphey's law - you have 50% chance of getting this right, and 90% chance of getting it wrong.
Tim Wescott wrote:

> Argh. So, I think I manage to get the UART outie hooked up to the USB > and/or RS232 converter outie (and innie to innie) well over half the time. > > And, I just did it again. The STM32F303 has a SWAP bit in its UART > configuration, to swap the TX and RX pins, but that would be cheating > (and besides, I did it with RTS/CTS as well). > > C'mon. Say that _you_ get it right all the time! >
I feel with you. The board I got finally today has the same problem. Fortunately it is just an USB-serial adapter for programming. Having a cable between with Rx/Tx swapped makes everything much more flexible. ;-) Th P-FET in sot23 lying upside down does not disturb anybody, either. -- Reinhardt
Michael Kellett wrote:

> Tim Wescott: >> Argh. So, I think I manage to get the UART outie hooked up to the USB > >> and/or RS232 converter outie (and innie to innie) well over half the > time. >> >> And, I just did it again. The STM32F303 has a SWAP bit in its UART >> configuration, to swap the TX and RX pins, but that would be cheating > >> (and besides, I did it with RTS/CTS as well). >> >> C'mon. Say that _you_ get it right all the time! >> >> -- >> >> Tim Wescott >> Wescott Design Services >> http://www.wescottdesign.com > > I get it right every time (of course) but make up for it my mixing up > genders of D connectors so you have to solder them to the other side of > the PCB. > I do get into problems when interfacing with other boards - my TX is TX > but they think that their TX is as well ! > > I once worked a lot with an engineer (he was the boss) who reckoned > that the odds of getting it right were so little improved by thinking > about it that it was a waste of effort since it took so little time to > cross the wires in the cable. (They made bespoke production lines.)
Without thinking about it, the odds are 50% for right and 50% for wrong. Thinking about it moves this more to the wrong side. -- Reinhardt
On 06/30/2015 05:43 PM, David Eather wrote:
> On Wed, 01 Jul 2015 07:17:08 +1000, Tim Wescott > <seemywebsite@myfooter.really> wrote: > >> Argh. So, I think I manage to get the UART outie hooked up to the USB >> and/or RS232 converter outie (and innie to innie) well over half the >> time. >> >> And, I just did it again. The STM32F303 has a SWAP bit in its UART >> configuration, to swap the TX and RX pins, but that would be cheating >> (and besides, I did it with RTS/CTS as well). >> >> C'mon. Say that _you_ get it right all the time! >> > > I used to get it right all the time. I had a port monitor/configure > thingy - I just kept flipping switches until I got the maximum number of > lit leds and whoosh went the data. Checking the switches then told me > how to wire up a permanent cable. One of the best bits of kit possible > for RS232 and about $10!
I still have a Smart Cable that does that. For my own stuff, I used to rely heavily on Jan Axelson's "Serial Port Complete". Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
On Tue, 30 Jun 2015 16:17:08 -0500, Tim Wescott
<seemywebsite@myfooter.really> wrote:

>Argh. So, I think I manage to get the UART outie hooked up to the USB >and/or RS232 converter outie (and innie to innie) well over half the time. > >And, I just did it again. The STM32F303 has a SWAP bit in its UART >configuration, to swap the TX and RX pins, but that would be cheating >(and besides, I did it with RTS/CTS as well). > >C'mon. Say that _you_ get it right all the time!
Just have three or four people each check it five times. -- John Larkin Highland Technology, Inc picosecond timing laser drivers and controllers jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On Wed, 01 Jul 2015 22:14:42 +0800, Reinhardt Behm
<rbehm@hushmail.com> wrote:

>Tim Wescott wrote: > >> Argh. So, I think I manage to get the UART outie hooked up to the USB >> and/or RS232 converter outie (and innie to innie) well over half the time. >> >> And, I just did it again. The STM32F303 has a SWAP bit in its UART >> configuration, to swap the TX and RX pins, but that would be cheating >> (and besides, I did it with RTS/CTS as well). >> >> C'mon. Say that _you_ get it right all the time! >> > >I feel with you. The board I got finally today has the same problem. >Fortunately it is just an USB-serial adapter for programming. >Having a cable between with Rx/Tx swapped makes everything much more >flexible. ;-) > >Th P-FET in sot23 lying upside down does not disturb anybody, either.
Except they guy who has to put it there.
On 2015-06-30 2:17 PM, Tim Wescott wrote:
> Argh. So, I think I manage to get the UART outie hooked up to the USB > and/or RS232 converter outie (and innie to innie) well over half the time. > > And, I just did it again. The STM32F303 has a SWAP bit in its UART > configuration, to swap the TX and RX pins, ...
Ah, the oops register bit :-)
> ... but that would be cheating > (and besides, I did it with RTS/CTS as well). > > C'mon. Say that _you_ get it right all the time! >
So far, yes, knocking on wood. I am surprised that there isn't an oops chip for this. Like a crosspoint gender changer SMT thingie that you can buy in a through and a cross version. After all, they used to make oops transistors in the early days of SMT when people messed up the SOT23 footprint. Not sure if they still make those. -- Regards, Joerg http://www.analogconsultants.com/
krw wrote:

> On Wed, 01 Jul 2015 22:14:42 +0800, Reinhardt Behm > <rbehm@hushmail.com> wrote: > >>Tim Wescott wrote: >> >>> Argh. So, I think I manage to get the UART outie hooked up to the USB >>> and/or RS232 converter outie (and innie to innie) well over half the >>> time. >>> >>> And, I just did it again. The STM32F303 has a SWAP bit in its UART >>> configuration, to swap the TX and RX pins, but that would be cheating >>> (and besides, I did it with RTS/CTS as well). >>> >>> C'mon. Say that _you_ get it right all the time! >>> >> >>I feel with you. The board I got finally today has the same problem. >>Fortunately it is just an USB-serial adapter for programming. >>Having a cable between with Rx/Tx swapped makes everything much more >>flexible. ;-) >> >>Th P-FET in sot23 lying upside down does not disturb anybody, either. > > Except they guy who has to put it there.
That'S me for the five prototypes. As far as I know my customer I expect him with change requests after seeing the prototypes. So he will pay for fix. There is an old saying attributed to IBM sales guys: The customer will pay for it, he just may not know when and how. -- Reinhardt
On 2015-07-01 9:47 PM, Reinhardt Behm wrote:
> krw wrote: > >> On Wed, 01 Jul 2015 22:14:42 +0800, Reinhardt Behm >> <rbehm@hushmail.com> wrote: >> >>> Tim Wescott wrote: >>> >>>> Argh. So, I think I manage to get the UART outie hooked up to the USB >>>> and/or RS232 converter outie (and innie to innie) well over half the >>>> time. >>>> >>>> And, I just did it again. The STM32F303 has a SWAP bit in its UART >>>> configuration, to swap the TX and RX pins, but that would be cheating >>>> (and besides, I did it with RTS/CTS as well). >>>> >>>> C'mon. Say that _you_ get it right all the time! >>>> >>> >>> I feel with you. The board I got finally today has the same problem. >>> Fortunately it is just an USB-serial adapter for programming. >>> Having a cable between with Rx/Tx swapped makes everything much more >>> flexible. ;-) >>> >>> Th P-FET in sot23 lying upside down does not disturb anybody, either. >> >> Except they guy who has to put it there. > > That'S me for the five prototypes. As far as I know my customer I expect him > with change requests after seeing the prototypes. So he will pay for fix. > There is an old saying attributed to IBM sales guys: The customer will pay > for it, he just may not know when and how. >
Hopefully this customer doesn't read Usenet :-) -- Regards, Joerg http://www.analogconsultants.com/
On Thu, 02 Jul 2015 12:47:16 +0800, Reinhardt Behm
<rbehm@hushmail.com> wrote:

>krw wrote: > >> On Wed, 01 Jul 2015 22:14:42 +0800, Reinhardt Behm >> <rbehm@hushmail.com> wrote: >> >>>Tim Wescott wrote: >>> >>>> Argh. So, I think I manage to get the UART outie hooked up to the USB >>>> and/or RS232 converter outie (and innie to innie) well over half the >>>> time. >>>> >>>> And, I just did it again. The STM32F303 has a SWAP bit in its UART >>>> configuration, to swap the TX and RX pins, but that would be cheating >>>> (and besides, I did it with RTS/CTS as well). >>>> >>>> C'mon. Say that _you_ get it right all the time! >>>> >>> >>>I feel with you. The board I got finally today has the same problem. >>>Fortunately it is just an USB-serial adapter for programming. >>>Having a cable between with Rx/Tx swapped makes everything much more >>>flexible. ;-) >>> >>>Th P-FET in sot23 lying upside down does not disturb anybody, either. >> >> Except they guy who has to put it there. > >That'S me for the five prototypes. As far as I know my customer I expect him >with change requests after seeing the prototypes. So he will pay for fix. >There is an old saying attributed to IBM sales guys: The customer will pay >for it, he just may not know when and how.
Ofr prototypes, you made the mistake - own it. ;-) Production frowns on such things though. BTDT.