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Cats_Cats_Cats
11-18-2009, 03:15 AM
USB/Serial http://www.parallax.com/Store/Microcontrollers/BASICStampProgrammingKits/tabid/136/ProductID/320/List/1/Default.aspx?SortField=ProductName,ProductName

USB http://www.parallax.com/Store/Microcontrollers/BASICStampProgrammingKits/tabid/136/ProductID/297/List/1/Default.aspx?SortField=ProductName,ProductName

USB/Serial vs USB

Why two separate kits?

Where on the pic in this image does the USB connection go?·http://www.parallax.com/Portals/0/Images/Prod/2/278/27807-M.jpg

Is it those "black boxes" on the upper right of the board?

Is there a possibility for more devices to be connected there in a series fashion, as in


wikipedia said...

USB devices are linked in series through hubs. There always exists one hub known as the root hub, which is built into the host controller. So-called sharing hubs, which allow multiple computers to access the same peripheral device(s), also exist and work by switching access between PCs, either automatically or manually. They are popular in small-office environments. In network terms, they converge rather than diverge branches.

See: http://en.wikipedia.org/wiki/Universal_Serial_Bus#Overview

Are those black boxes USB-B s, on the right? http://upload.wikimedia.org/wikipedia/commons/thumb/6/67/USB.svg/180px-USB.svg.png

The connector cable in the image looks like a USB-A; where does it plug in on that pic of the board?

It looks to me like I have 3 USBs on my computer, one which I want to leave connected to my webcam. It also looks like I have room for an RS232, as well as something else rather large (don't know the connector type). I also have a couple of FireWires, not that it matters.

Thank you. I'm sure I will come up with more questions. I'm trying to decide just·what to buy.·http://forums.parallax.com/images/smilies/smile.gif

Mike Green
11-18-2009, 03:24 AM
The USB/Serial kit is basically a serial version that includes a serial to USB adapter. The USB kit has the same serial to USB adapter built-in to the board. Functionally, they're equivalent. Both of them use what's called a mini-USB-A socket with a matching cable that has a mini-USB-A plug on one end and a full size USB-A plug on the other end. The USB-A plug goes into your computer or into a USB hub.

If you have an RS232 connector on your computer, you can use that with the USB/Serial version of the kit. You just need a matching cable. If you get the Serial version of the kit, it will come with the cable that goes into your RS232 connector.

The "black" areas on the board are connectors for servo motors, one of which comes with the kit. These connectors can be used for other things as well, but are normally used for servo motors. They supply power, ground, and a control signal straight from one of the Stamp I/O pins.

The picture is of a USB kit and the mini-USB-A socket is around the middle of the left-hand side of the board. There is no connecting of USB devices in "series". You need a hub to do that. The hub provides power for the USB device and buffers the signal. Hubs can seem to be connected in series although there's always buffering involved, so it's not a direct series connection. Devices can have a built-in hub so they seem to allow connection in series, but it's the built-in hub that's actually doing the work.

Post Edited (Mike Green) : 11/17/2009 7:34:33 PM GMT

Cats_Cats_Cats
11-18-2009, 04:15 AM
Mike Green said...
The USB/Serial kit is basically a serial version that includes a serial to USB adapter. The USB kit has the same serial to USB adapter built-in to the board. Functionally, they're equivalent. Both of them use what's called a mini-USB-A socket with a matching cable that has a mini-USB-A plug on one end and a full size USB-A plug on the other end. The USB-A plug goes into your computer or into a USB hub.

If you have an RS232 connector on your computer, you can use that with the USB/Serial version of the kit. You just need a matching cable. If you get the Serial version of the kit, it will come with the cable that goes into your RS232 connector.

The "black" areas on the board are connectors for servo motors, one of which comes with the kit. These connectors can be used for other things as well, but are normally used for servo motors. They supply power, ground, and a control signal straight from one of the Stamp I/O pins.

The picture is of a USB kit and the mini-USB-A socket is around the middle of the left-hand side of the board. There is no connecting of USB devices in "series". You need a hub to do that. The hub provides power for the USB device and buffers the signal. Hubs can seem to be connected in series although there's always buffering involved, so it's not a direct series connection. Devices can have a built-in hub so they seem to allow connection in series, but it's the built-in hub that's actually doing the work.
Thank you for that. I went looking for an article on USB hubs and found one (http://en.wikipedia.org/wiki/USB_hub).

Since I'm trying to decide which is the best buy, and since USB huhs don't cost much (my brief investigation revealed some as low as $6 new) (http://www.google.com/search?hl=en&source=hp&q=usb+hub&aq=f&oq=&aqi=g10) , and since I have only one RS232 port, perhaps the USB kit would be the·best choice of the two.

I still have to decide on whether or not to go even cheaper (http://www.parallax.com/Store/Microcontrollers/BASICStampProgrammingKits/tabid/136/ProductID/313/List/0/Default.aspx?SortField=ProductName,ProductName), although I am very tempted to go straight for the plain·USB kit.

Probably I will be back with more questions after a while. Thank you Mike! http://forums.parallax.com/images/smilies/smile.gif

Cats_Cats_Cats
11-18-2009, 07:58 AM
Aha! I have a new question: is that an RS232 cable in this pic:
http://www.parallax.com/Portals/0/Images/Prod/9/900/90005-M.jpg
RS232 cable?

It looks like it to me.

Cats_Cats_Cats
11-18-2009, 09:32 AM
Bump - Does anybody know? RS232??? http://forums.parallax.com/images/smilies/confused.gif

Mike Green
11-18-2009, 09:42 AM
1) Do not "bump" messages. It's poor form at best. These forums (fora?) are staffed primarily by volunteers and even Parallax staff have other duties. Be patient ... it takes a while.

2) Yes, the cable in the picture you showed is the RS232 serial cable I mentioned earlier.

Cats_Cats_Cats
11-18-2009, 09:52 AM
Mike Green said...
1) Do not "bump" messages. It's poor form at best. These forums (fora?) are staffed primarily by volunteers and even Parallax staff have other duties. Be patient ... it takes a while.

2) Yes, the cable in the picture you showed is the RS232 serial cable I mentioned earlier.
Thank you. I'm sorry I bumped my post, I won't do it again. http://forums.parallax.com/images/smilies/blush.gif

I think I've decided on the USB kit then. It may take me a while. It doesn't look like payment is very easy. I've got the wrong kind of credit card, and it doesn't look like Paypal is an option.

Does anybody have any suggestions for quick payment?

Cats_Cats_Cats
11-18-2009, 10:13 AM
Well, I guess I've got an order quotation coming, whatever that means . . .

Guess that's it for now. I'll probably have more questions later . . .

Thank you Mike! http://forums.parallax.com/images/smilies/smile.gif