Based on 100 such incidents per computer user per year, and three wasted seconds per time, and 200 million computer users, I get that this wastes 16 million man-hours per year. Just because the plug was not made asymmetrical.
---
Alex expands:
You think that is bad, at least it is keyed to be the right way around.
Have you ever considered how dangerous it is to have a connector which physically will fit either way round, but not so electrically. The amount of time I've lost because a connector was in backwards, not to mention the cases where this causes board damage.
There is an interesting JTAG/OnCE connector, for cost implemented as simply as possible, unhooded and unkeyed. It is used for programming chips, like Freescale DSP's. One programmer is made by McGraigor , and available from Freescale and direct from McGraigor. The one from Freescale has a pin embedded so the connector can only be used one way around. The McGraigor direct version is un-keyed.
All well and good until you see the Freescale reference design, and they do not show to use a keyed header, so you end up not being able to plug in directly.
I have found, on my laptop, that a 3.5mm audio jack will slip into the 7in1 card slot which is right below the audio ports. The power barrel connector will fit inside the ethernet RJ-45 socket too.
In the PreUSB days I found Apples DIN8 serial connectors to be hard to line up, and not all AppleTalk dongles had an indicator to show the top. Also PS2 mouse and keyboard ports, dammit, once the box is under the desk I can't see which way up, or which is Mouse and which is key!
Have you ever tried to connect a parallel printer with a DB25M to DB25F only to find it is a single RS232 with only 9 of the 25 wires.
Have you ever plugged in an ethernet cable only to find it is a crossover not a straight.
Have you ever tried to plug a PBX phone into the wall using a POTS cable?
I can't think of a single easy to plug in, unambiguous connector which does not rely on clear sight of where you are connecting it. heck, the other day I plugged a walwart into 110V a bench power strip only to see that physically I had one pin in the socket and the other hanging over the side, I'd missed by an inch!
Actually, I have had easy to use, absolutely positive plugs, all were in industrial applications, and each as big as a PC mouse. Still in answer to you comment, it must be many times the wastage if you take in all other connector types.
Oh, here is a tidbit:
"A: The USB-IF does not allow the logo to be on the overmold of either the "A" or "B" connector of a cable assembly. The standard USB trident must be on the top of both plug overmolds as described in chapter 6 of the USB 2.0 specification. Any cable assembly found with the hi-speed logo on the plug overmold will be deemed non-compliant."
So the type A plug is asymmetrical, the logo is on the top! I can't find docs on where the port is labeled on the device.
1 comment:
You think that is bad, at least it is keyed to be the right way around.
Have you ever considered how dangerous it is to have a connector which physically will fit either way round, but not so electrically. The amount of time I've lost because a connector was in backwards, not to mention the cases where this causes board damage.
There is an interesting JTAG/OnCE connector, for cost implemented as simply as possible, unhooded and unkeyed. It is used for programming chips, like Freescale DSP's. One programmer is made by McGraigor , and available from Freescale and direct from McGraigor. The one from Freescale has a pin embedded so the connector can only be used one way around. The McGraigor direct version is un-keyed.
All well and good until you see the Freescale reference design, and they do not show to use a keyed header, so you end up not being able to plug in directly.
I have found, on my laptop, that a 3.5mm audio jack will slip into the 7in1 card slot which is right below the audio ports. The power barrel connector will fit inside the ethernet RJ-45 socket too.
In the PreUSB days I found Apples DIN8 serial connectors to be hard to line up, and not all AppleTalk dongles had an indicator to show the top. Also PS2 mouse and keyboard ports, dammit, once the box is under the desk I can't see which way up, or which is Mouse and which is key!
Have you ever tried to connect a parallel printer with a DB25M to DB25F only to find it is a single RS232 with only 9 of the 25 wires.
Have you ever plugged in an ethernet cable only to find it is a crossover not a straight.
Have you ever tried to plug a PBX phone into the wall using a POTS cable?
I can't think of a single easy to plug in, unambiguous connector which does not rely on clear sight of where you are connecting it. heck, the other day I plugged a walwart into 110V a bench power strip only to see that physically I had one pin in the socket and the other hanging over the side, I'd missed by an inch!
Actually, I have had easy to use, absolutely positive plugs, all were in industrial applications, and each as big as a PC mouse. Still in answer to you comment, it must be many times the wastage if you take in all other connector types.
Oh, here is a tidbit
"A: The USB-IF does not allow the logo to be on the overmold of either the "A" or "B" connector of a cable assembly. The standard USB trident must be on the top of both plug overmolds as described in chapter 6 of the USB 2.0 specification. Any cable assembly found with the hi-speed logo on the plug overmold will be deemed non-compliant."
So the type A plug is asymmetrical, the logo is on the top! I can't find docs on where the port is labeled on the device.
Post a Comment