[Discussion] USB to parallel cable observation

[Douglas Clark]

Carl,

I am running ECS 1.2 GA and with an HP Scanjet 6200C. The scanner has both SCSI and 
USB connections. I tried hooking the scanner up via USB and experienced extremely long 
boot up times with the scanner connected that way. I eventually gave up connecting the 
scanner via USB and went back to SCSI - which works great.

Other USB "issues": I have a multi-card USB reader. The reader/ECS will recognize and an 
SD just fine when the card reader is plugged directly into one of the computer's USB ports, 
but when the card reader is plugged into my (powered) USB hub ECS will never recognize 
the SD card on insertion. However, I can put the same SD card into one of those little SD 
to USB devices and plug that device into the hub and ECS recognizes the card just fine.

I suspect there are compatibilty issues between different USB devices - or combinations of 
USB devices. Some years ago I was running a broadcast FAX business. What I discovered 
is that not all fax machines/modems are compatible with each other. Must people wouldn't 
notice that with a single fax machine/modem sending out the occassional fax. But when 
you send out hundreds you find fax machines that cannot connect to other fax 
machines/modems. Since I had a number of different fax modems my solution was to route 
those fax numbers to modems that were compatible with the receiving fax machine. All this 
is to say that equipment that appears to be compatible from limited experience can in fact 
turn out to not be very compatible. I suspect these types of issues exist in the USB world, 
just as they did/do in the fax world. 

(BTW - I could run 8 fax modems full speed with OS/2 v 3 on a 486SX 20 MHZ machine 
with 8 MB of RAM. For awhile I was running multiple fax modems off of a 386/20mhz 
machine with 6 MB of ram. Pretty impressive  - and OS/2 still is.)


Doug Clark






On Fri, 19 Dec 2008 20:38:44 -0500 (EST), Carl Gehr wrote:

>I have a worse situation!
>
>I have a new system with a fresh eCS 2.0 RC5.  It should have all the
>latest drivers, video and otherwise.
>
>If I have the USB/Parallel device plugged at boot-time, the system
>HANGS completely. Now, it may be related to the video driver [the
>latest SNAP], because the next expected set of messages on the screen
>during the boot, would be the SNAP messages.  [It is possible that the
>messages indicating loading of the UNICODE may also be missing, but I
>can't remember for sure.]  Unplugging the USB/Parallel and restarting
>the boot and it works fine.
>
>If I wait to plug the USB/Parallel in until after the boot is complete,
>then the printer is not recognized... similar to what you described