USB-Blaster Stops Working After Sitting Idle For Several Minutes

Hello,

I am using Linux, Quartus II 15.0.1, and a USB blaster to program FPGAs. See Environment Details below for more information.

It starts out working just fine. But if I leave the system sit for a few minutes, it won't read the JTAG chain anymore. I have to unplug and replug the USB cable 3 to 10 times to get it to work again, see below.

I have been using a USB Blaster from Altera, Rev. B, a "Sunshine Blaster" made in China, and a generic USB Blaster Rev C, same behavior on all 3.

Any ideas?

initially works (if i put this in a loop with a sleep every 10 seconds it will go for hours):

user@system:/opt/quartus_15/quartus/bin>./jtagconfig

1) USB-Blaster [3-11]

13642223

020A30DD 5M1270Z/EPM1270

and even programs correctly:

Info (209060): Started Programmer operation at Thu Jul 30 10:45:24 2015

Info (209017): Device 2 contains JTAG ID code 0x020A30DD

Info (209018): Device 2 silicon ID is ALTERA04-1

Info (209044): Erasing MAXII/MAXV configuration device(s)

Info (209023): Programming device(s)

Info (209021): Performing verification on device(s)

Info (209011): Successfully performed operation(s)

Info (209061): Ended Programmer operation at Thu Jul 30 10:45:29 2015

Info: Quartus II 64-Bit Programmer was successful. 0 errors, 0 warnings

times out:

user@system:/opt/quartus_15/quartus/bin>./jtagconfig; sleep 180; ./jtagconfig

1) USB-Blaster [3-11]

13642223

020A30DD 5M1270Z/EPM1270

1) USB-Blaster [3-11]

Unable to read device chain - JTAG chain broken

unplugging and replugging usb between each call to jtagconfig:

user@system:/opt/quartus_15/quartus/bin>./jtagconfig

1) USB-Blaster [3-11]

Unable to read device chain - JTAG chain broken

user@system:/opt/quartus_15/quartus/bin>./jtagconfig

1) USB-Blaster [3-11]

Unable to read device chain - JTAG chain broken

user@system:/opt/quartus_15/quartus/bin>./jtagconfig

1) USB-Blaster [3-11]

Unable to read device chain - JTAG chain broken

user@system:/opt/quartus_15/quartus/bin>./jtagconfig

1) USB-Blaster [3-11]

13642223

020A30DD 5M1270Z/EPM1270

And then it will work again until I leave it idle for about 3 minutes.

environment details:

Quartus: Version 15.0.1 Build 150 06/03/2015 SJ Full Version

CentOS Linux release 7.1.1503 (Core)

uname -r: 3.10.0-229.4.2.el7.x86_64

I see the same thing on CentOS 6 with Quartus II 8.0