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Mh721 broken usb replacement HELP!!

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Good evening,

I tripped and broke my girlfriend’s USB driver, how to fix this ?

 If I bet a mother board will it resolve this problem?

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the mk2 version of mainboard is on the uscutter site but there have been around 4 different mainboards in the MH series plotters so make sure you order the right one if you can find it - uscutter doesn't appear to sell the other 3 anymore and they are not interchangeable 

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Does the MH have a serial port?

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Good morning.

Many years ago, with my MH unit, I caught my foot on the USB cable and broke the USB PORT connector.

That led me to quickly order a replacement port board (called Input/Output). That I/O port board is separate from the motherboard. If you open that side panel of the machine, you'll access it. (motherboard is in the bottom of the cutter).

By the way, haumana, the better question would be  -- Does your COMPUTER have a serial DB9 port?!!  (MH has serial port)

OK, so guess what? Yep, USCUTTER does not currently have a replacement MH port board available for order.

That leaves you with a problem, and perhaps you'll be able to solve it with a local electronics repair place, and just have them solder a new USB connector into the existing I/O board, if possible.

This is the standard part --- Printer-USB-interface-BF90-degree-B-fema

 

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If the OP doesn't doesn't have a serial, than that what a keyspan is for, but at the least there is another means to connect to the cutter.

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Years ago, I owned a laptop computer that didn't have the serial port built-in, but it did contain a thing called a PCMCIA slot. That allowed me to insert a serial port within a PCMCIA card. Ahhhh, legacy technology! Gotta love it.

I'm excited to see wireless bluetooth being introduced to cutters, that is a nice thing, to be sure.

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heck, hopefully they come back to see the info posted . . . signed up, posted and disappeared 8 minutes later and has not returned :/

 

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Motherboard part = $100 (and it has nothing to do with the issue of the I/O port)

USB jack replacement part = $1. (and this should work)

Hey, we can't be faulted for trying. Not everyone who drifts into this saloon wants a cold beer. Some of them just want to eat the free salted peanuts and leave.

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21 minutes ago, slice&dice said:

Motherboard part = $100 (and it has nothing to do with the issue of the I/O port)

USB jack replacement part = $1. (and this should work)

Hey, we can't be faulted for trying. Not everyone who drifts into this saloon wants a cold beer. Some of them just want to eat the free salted peanuts and leave.

Have you found a source for the first 3 versions of the main board of needed?     I agree at least 2 versions had the usb on a separate I/o board but couldn’t tell you which ones without opening the plotter.  Also do you remember how to identify the different versions of the boards?  As I recal it was different placement of the plugs on the boards that identified which one you needed 

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Bit late to the party, and seeing how the OP hasn't come back, but I would forget about the USB and just get a tripp-lite adapter and use the comm port. More reliable connection and doesn't involve trying to replace any electronics. Not that any of that is that hard, but it does scare a lot of people.

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I just had to get a tripp lite. My usb just t kinda fell off cause they are barely soldered on the board. 

 Now I am having the problem of the i formation is coming to the cutter TOO fast. 

I print from small the large sections like 24x24. Sometimes with a lot of cuts and info. The USB wasn't a problem. Now it trips up and just starts cutting a straight line through my designs.

How do I fix this with the Trip lite or lowering my computer USB output?

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check the baud rate in your cutting software.

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Also, do you have the stand grounded to the plotter? Lines through the design can be caused by static some times.

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Yes its grounded. Never had static problems. Its due to moving from the broken barely hanging USB to the other port. 

Never had this problem using USB. 

Lowered the baud and it helps some but only gives 4800 as the lowest. I dont know how to slow the iformation rate. These cutters do not seem to handle information sent to them quickly. Guess it is a ram problem. 

 

I have to break my designs into so many pieces it is too cumbersome. 

 

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Lowering the baud, or just randomly changing it is not going to help. You need to set it to the value the cutter is setup for. To fast or to slow and it just won't work. With the software setup correctly it will send data to the cutter, the cutter will respond to the computer that is received it and if the memory buffers are full, it'll tell the computer to wait before sending the next packet. If the comms are setup correctly it will not send the data "too fast".

What software are you using? And where did you change the baud rates, in the software or in windows device manager?

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Drives me nuts. I just cut 10 24 inch lines of text with no problem. Try and cut 2 and sends a straight diagonal line. Absolutely random. I'm losing so much material cause my usb just fell off the board. 

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Does that software give you the option to change the data Bits, Stop Bits, and Parity Option? I'll need to double check what they should be set to when I get home if they are something you can change. Do you have Flow Control set to Hardware?

Have you opened the cutter and looked at the USB connector? If it was stressed enough to break off it may have damaged more than just the USB connection.

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No it doesn't give me the option to change any of that. I do not have a flow chart set to hardware. I have what came with the cutter. Its the MH721 - MK2. 

I did have to take the case off due to the usb just stopped working. In doing so the USB just fell off the board into my hand. I had to go buy a trip lite to get it to work but now as discussed the data is all whacked. The SCALP program even when the machine is off will continue to feed information through the USB. I have to stop the machine if it starts to fail a cut to try and reserve material. 

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My next suggestion would be try some different software. SignBlazer is free and works with the MH, there are links to it on the forum, a quick search should find one for you. You could also try Inkscape. It is a design program does have the ability to cut at a very simplistic level. See if either of those behave differently.

One other question, what OS on your computer are you running?

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