10 Feb
2006
10 Feb
'06
8:21 p.m.
Tony Duell wrote:
Well, the article looked like they used 75160/75161 as the GPIB bus
driver pair. IIRC, if you used
75160/75162, then the HPIB side could be a bus controller. Of course,
I thought the GPIB side already was a controller. Surely it's not a
mailbox (to use the HP terminology) to link a GPIB controller to a USB host.
I thought you could use the 75161 as the control buffer for a controller,
btu there was something you couldn't then do (is it pass control to
another device ?) But I would have to check the data sheet to be sure.
I know
that there are a number of HP enthusiasts here. This item was in
the current EDN online and I thought it might interest someone:
http://www.edn.com/article/CA6290453.html?spacedesc=designideas
From the subject: line, I asusme this is a device
to link GPIB
peripherals to a USB host, and not the much more useful (to me)
interface
to link USB peripherals to an HPIB controller...
-tony
the hardware here is very
simple, and all the smarts are in the microcontroller, so though a
"Simple Matter Of Programming"
you could have commands from the HPIB going on to USB peripherals or
reverse with the original
hardware, or you could have a master on the HPIB bus with the other
driver chip...
My worry is in the very asymmetric (logically) nature of the USB
interface. I haven't really looked at it, but I've got the impression
that moat of the micorcotnrollers with USB interfaces can only be used as
slave devices, and that rather more smarts are needs to make a host. If
not, and you can use one of these microcontrollers to talk to USB
peripherals, I am going to have to give it a go.
mode, so you still only
get 12MBPS)
As if that would be a problem in this application :-)
-tony