Multiple USB Blasters on the same PC

[Altera_Forum]

The problem is that Altera provides each device with the same serial number. This should be no problem unless one wants to connect several USB Blaster devices to the same computer. 

 A new serial number can be programmed wit the MProg tool. It can be downloaded from http://www.ftdichip.com/resources/utilities.htm (http://www.ftdichip.com/resources/utilities.htm).  When started, download the EEPROM content from the USB Blaster you want to modify. Save it to disk and erase the EEPROM. During reprogramming with the old content, MPROG will provide a new, random serial number.  I have done this to several USB Blaster devices without any troubles. Everything works fine, but as always:  THIS CAN MAKE YOUR USB BLASTER NON-FUNCTIONAL - SO DO IT AT YOUR OWN RISK !!!

[Altera_Forum]

Well that's a timely post. Can you post the template file for programming the blaster, ie what you uploaded from it using mprog? 

 I have an FTDI device on a board that I was programmng, but at the same time had left the usb-blaster plugged in. Guess what - mprog programmed the wrong device and I now have a non-functioning blaster.  There's a lesson there somewhere.

[Altera_Forum]

Well I got the blaster back in action by trial and experiment with the MProg settings. But the final step was to search the registry for a trace of the original driver install. I found it with serial number (FT)a09400f0. Until I used this number the blaster was not detected by jtagconfig. 

 The other driver installs, one per serial number I tried, were in the registry but jtagconfig did not detect the blaster in these cases. So it would still be interesting to see the template you uploaded from the original blaster. It would be handy to have at least a pair of blasters on my PC.

[Altera_Forum]

If you have revb blaster - you must write REVB to user space area of FT245BM configuration eeprom.

[Altera_Forum]

here is the MPROG .ept file i got from the USB Blaster Rev C EEPROM: 

 [Basic Details] Device Type=3 VID PID Type=2 USB VID=09FB USB PID=6001 [USB Power Options] Bus Powered=1 Self Powered=0 Max Bus Power=150 [USB Serial Number Control] Prefix=91 Use Fixed Serial Number=0 Fixed Serial Number=91d28408 [USB Remote WakeUp] Enable Remote WakeUp=0 [Windows Plug and Play] Enable Plug and Play=0 [USB String Descriptors] Manufacturer=Altera Product=USB-Blaster [Programming Options] Only Program Blank Devices=0 [BM Device Specific Options] USB Version Number=0 Disable Serial Number=0 IO Pin Pull Down in Suspend=1 [Dual Device Specific Options A] RS 232 mode=1 245 FIFO mode=0 245 CPU FIFO mode=0 OPTO Isolate mode=1 High Current Drive=0 [Dual Device Specific Options B] RS 232 mode=1 245 FIFO mode=0 245 CPU FIFO mode=0 OPTO Isolate mode=0 High Current Drive=0 [Dual Device Driver Options A] Virtual Com Port Driver=1 D2XX Driver=0 [Dual Device Driver Options B] Virtual Com Port Driver=1 D2XX Driver=0   hope this helps...  Klaus

[Altera_Forum]

stonie: This file for UsbBlaster RevA!!! 

In MProg utility run read(not read and parce). And see string at offset 0x4e! With this string UsbBlaster identified as revb and others. This string is revision.

[Altera_Forum]

Thank you stonie and nvs. 

All is well with my RevA blaster, but have ordered another which no doubt will be RevB.  I had no idea the blaster used the same chip as my application, and even less that mprog would re-program something it was not plugged into.  While the solution is to unplug the blaster while setting up my board, it does raise a question as to why the blaster, as a commercial product, is not protected from over-writing. Maybe it's not possible. I will investigate this on my board as I don't want it to be exposed in this way on the final product.