[Coco] DriveWire 3

[Gene Heskett]

On Saturday 04 April 2009, Roger Taylor wrote:
>At 03:14 PM 4/4/2009, you wrote:
>>On Saturday 04 April 2009, J.P. Samson wrote:
>> >On Apr 4, 2009, at 12:25 PM, Roger Taylor wrote:
>> >> First, let me mention that I sell HQ bitbanger cables.  I test them
>> >> not only at 115200 bps, but at twice that speed using a certain
>> >> person's unannounced bitbanger routines.  Not only that, but my
>> >> cables are tested using an IOGear USB to Serial adaptor.  With that
>> >> being said, I doubt that my cables are the reason I'm having trouble
>> >> with DW3.
>> >
>> >I believe IOGear uses Prolific chipsets for their USB-to-serial
>> >adapters, yes?
>>
>>Hoo boy, if they do, that is Rogers problem for sure.  FTDI chipsets are
>> the magic twanger.
>
>Why does CoCoNet not have a problem with the adaptor?

Probably because once you wake it up, it might be ok?  I don't know for sure, 
but they are a huge PITA in situations where it might not have a byte to send 
for several hours, like when using them with heyu.  Or trying to monitor the 
data stream coming out of a UPS, that is moderately busy since the UPS will 
normally issue a status update at about 1 second intervals to the monitoring 
daemon.  In that service, the logs will record that the device has died, and 
then showed up again, several times a minute, a great way to generate a 200 
megabyte log in 2 or 3 days.  The machines uptime will be from whenever you 
enable the UPSD to issue graceful shutdown orders because there has been a 
power failure (so it thinks due to the error) when the first error occurs.

If you put a tee on the data coming out, what you see is that the first, 
attention byte in a string of 4 or 5 (heyu) to maybe 75 from the ups, is 
missing from the data stream. 

Plug in an FTDI adaptor and everything works as expected.  2 weeks later the 
last log entry will still be where it discovered the new device when you 
plugged it in.  They Just Work(TM).

This has been researched at length on the heyu list, so I'm not just a voice 
in the wilderness about this.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
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-Ed Howdershelt (Author)
I must Create a System, or be enslav'd by another Man's;
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