JTAG chain with Cyclone V, MAX V, and Texas Instruments AM3559.

[Altera_Forum]

Hi 

 My board will have three JTAG devices: Cyclone V, MAX V, and Texas Instruments AM3559. I would like to make a JTAG chain with these 3 devices. Will it work? I have seen that this chain is possible by JTAG definition. Some forum answers to use "JTAG BYPASS" configuration... But could there be a development tools for these devices that does not support it?  thank you  Rogerio.

[Altera_Forum]

You need to ensure that your JTAG I/O voltages match up between devices.  

Also a good idea to buffer your TMS and TCK signals.  I have done this myself with multiple Altera FPGAs and Analog Devices SHARCs and it works fine. I did have some trouble early on but it was mainly down to (lack of) consideration of the power sequencing of the SHARC and TRST wiring.  Also, make sure you read the relevant handbooks for JTAG wiring schemes.

[Altera_Forum]

Thank you for your response. 

 Rogerio.

[Altera_Forum]

Hi Rogerio, 

 I'm also thinking of using the Texas Instruments AM3559. I plan on interfacing the local bus of the processor to a Cyclone IV GX device. Have you located any of the processors in stock anywhere? The XAM3559 is used on the BeagleBone, but the production devices are not available yet.  I might create a BeagleBone cape with a CPLD to confirm the bus interface operates correctly.  Cheers, Dave

[Altera_Forum]

Hi Dave, 

 Currently I have found some stock researching for AM3559 on findchips web page, and from ti AM3359 web page -> buy now -> distribuitor invertory.  Cheers  Rogerio

[Altera_Forum]

Hi Rogerio, 

  --- Quote Start ---   Currently I have found some stock researching for AM3559 on findchips web page, and from ti AM3359 web page -> buy now -> distribuitor invertory.   --- Quote End ---    Look again. They all indicate "No Stock".  I'm not going to stress over this too much. I don't need the devices for a few months. Worst-case I'll remove several devices from BeagleBone's and have the devices re-balled. However, you might not have that option, so I figured I'd mention the lack of stock of these devices.  Cheers, Dave

[Altera_Forum]

I appreciate your advice Dave. I trust this is a successful new device and the stocks will be available. But you are right, it may be a problem for now. I am reinforcing this concern in my project. 

Cheers, Rogerio.