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Starglow

JTAG HS3 compatible IDC ribbon cable....??

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Hello....I have a PCB mounted JTAG interface connector which is a 14-pin 2mm pitch Molex P/N: 87832-5622. I want to extend this interface off the PCB with a short 6" length of IDC ribbon cable, but am having a hard time finding a ribbon cable compatible connector that can support the JTAG HS3 interface side. I've contacted both Samtec and Molex directly, but neither had a viable solution. Yes...I can find IDC JTAG cables, but they are either the wrong pitch and/or incorrect gender to interface with the HS3. I can build my own IDC cables if I had the correct connectors which seems to be a very simple task, but has instead proven to be difficult. Please see the attached photo for reference.

Any suggestions....? 

Thanks.....! 8-)

 

JTAG HS3.PNG

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Hi @Starglow,

We do have a cable that will connect to the host board, https://store.digilentinc.com/jtag-2x7-ribbon-cable/, but it does not have the male header to connect to the JTAG HS3, and all of headers that Digilent sells have a 2.54 mm pitch rather than the 2.00 mm pitch that Xilinx choose for their JTAG integration. I did do a Digikey search (though you are welcome to browse your favorite source for these) for a list of compatible headers that should work in your situation; the only thing I was not able to specify in the search was the 0.5 mm square posts to ensure the pins remain secure in the plastic header.

Let me know if you have any questions about this.

Thanks,
JColvin

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Starglow --

I had a similar problem.  The ends of the Molex connectors are too close together to accept a normal 2mm ribbon connector.

For the short term, you could saw the ends of the connector off with a razor saw.

For the long term, we are using parts similar to 98424-G52-14LF from FCI.  It should accept either a ribbon cable or the HS3.

Specifically, we are successfully using an 98424-G52-18LF part on our board.  We use an 18-pin ribbon cable to connect a "debugger board" that contains all of the circuits that we didn't have room for on our product board.  The extra four pins are used for setting the Zynq boot mode, provide power to the debugger board, and control a debug LED.

The HS3 may be plugged into the center 14-pins of the connector in this scheme.  If you only add two additional pins, the alignment tab on the HS3 connector will not line up with the connector pins.

The following describes our test fixture:

    One 14-pin male connector for the HS3 programmer

    One 18-pin male connector (center 14 pins tied to the connector above)

    An 18-pin ribbon cable (female on both ends) to connect the unit under test to the connector above.

I hope this helps.

 

will be plugged into the test fixture (14-pin male), be connected to an 18-pin male connector, jumpered over to the unit under test using an 18-pin ribbon cable (both ends female), and plugged into the unit under test.  This is proven to work.

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1 hour ago, Don Koch said:

Starglow --

I had a similar problem.  The ends of the Molex connectors are too close together to accept a normal 2mm ribbon connector.

For the short term, you could saw the ends of the connector off with a razor saw.

For the long term, we are using parts similar to 98424-G52-14LF from FCI.  It should accept either a ribbon cable or the HS3.

Specifically, we are successfully using an 98424-G52-18LF part on our board.  We use an 18-pin ribbon cable to connect a "debugger board" that contains all of the circuits that we didn't have room for on our product board.  The extra four pins are used for setting the Zynq boot mode, provide power to the debugger board, and control a debug LED.

The HS3 may be plugged into the center 14-pins of the connector in this scheme.  If you only add two additional pins, the alignment tab on the HS3 connector will not line up with the connector pins.

The following describes our test fixture:

    One 14-pin male connector for the HS3 programmer - What connector are you using for this??

    One 18-pin male connector (center 14 pins tied to the connector above)

    An 18-pin ribbon cable (female on both ends) to connect the unit under test to the connector above.

I hope this helps.

 

will be plugged into the test fixture (14-pin male), be connected to an 18-pin male connector, jumpered over to the unit under test using an 18-pin ribbon cable (both ends female), and plugged into the unit under test.  This is proven to work.

Hi Don,

We have several test bed units and want to extend a 14-pin ribbon cable from the existing PCB JTAG header connector to outside the box so the top covers can be installed. If one of the EUT units has a problem, then we can connect the JTAG HS3 to the extended cable for debug. So the ribbon cable would be 14-pin female (PCB) to 14-pin boxed male (HS3). The PCB side is no problem, but apparently a 2MM 14-pin boxed male ribbon cable compatible connector does not exist, nor does a 14-pin male to female PCB gender changer adapter that would allow us to use the 2mm 14-pin female to female ribbon cable. We could probably adapt the 18-pin connector as you suggested, but it would not be ideal for our test setup. I plan to touch base with Xilinx to see what they recommend, if anything, but we may end up just building our own PCB adapter.

I appreciate your time and suggestions....!!

Thanks....! 8-)

 

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Starglow --

Like you, I found that there are no male 2mm ribbon cable connectors to use to connect to the HS3.  I used a PCB mount Molex 87832-1420 connector.

For another project, I came across this board, which is a pitch adapter:

https://oshpark.com/profiles/smartperson

image.thumb.png.d239af1f3852c8f19cfebfc921fe329c.png

Due to their size, they are relatively inexpensive.  The configuration on the right shows a pair of them ganged together to create a male to male 2mm adapter.

The board design was published, allowing OshPark to sell them to whomever wants them.

The through-hole 14-pin 2mm male connector is fairly easy to find (these are Sullins SBH21-NBPN-D07-ST-BK).  After clamping the two boards together,  pins from a standard 0.1" header were inserted, soldered, and trimmed off.  Not real pretty, but it works.  If you have the resources, you could simply make a small male-to-male board that is smaller.

Again, I hope this helps.

Don

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55 minutes ago, Don Koch said:

Starglow --

Like you, I found that there are no male 2mm ribbon cable connectors to use to connect to the HS3.  I used a PCB mount Molex 87832-1420 connector.

For another project, I came across this board, which is a pitch adapter:

https://oshpark.com/profiles/smartperson

image.thumb.png.d239af1f3852c8f19cfebfc921fe329c.png

Due to their size, they are relatively inexpensive.  The configuration on the right shows a pair of them ganged together to create a male to male 2mm adapter.

The board design was published, allowing OshPark to sell them to whomever wants them.

The through-hole 14-pin 2mm male connector is fairly easy to find (these are Sullins SBH21-NBPN-D07-ST-BK).  After clamping the two boards together,  pins from a standard 0.1" header were inserted, soldered, and trimmed off.  Not real pretty, but it works.  If you have the resources, you could simply make a small male-to-male board that is smaller.

Again, I hope this helps.

Don

WOW....I think that setup just may do the trick if I can still get the parts. I will check into this.

Thanks Don.....!! You have been very helpful and hopefully I can stop pulling my hair out now...LOL 8-)

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