Usrp rev 3


#1

Does the USRP Rev 3 (1-3-2005) not handle the RFX boards? I guess it’s
been two years…

-Dan


#2

Dan H. wrote:

Does the USRP Rev 3 (1-3-2005) not handle the RFX boards? I guess it’s
been two years…

All RFX boards currently shipping are configured for MIMO_B mode, which
requires a Rev 4 or higher USRP (serial number greater than 500).

If you wish to use it with a USRP with a serial number below 500 you
will need to do the following:

Remove R115 (zero ohms) and place it at R116
Remove R36 (zero ohms) and place it at R34
Put the RFX on a USRP (side A) and run the following:

   usrp/host/apps/burn-db-eeprom -f -A -t rfxYYYY_mimo_a

        where YYYY is the board you have (i.e. 400, 900, 1200, 1800,

or 2400).

Matt


#3

Matt E. wrote:

   usrp/host/apps/burn-db-eeprom -f -A -t rfxYYYY_mimo_a

        where YYYY is the board you have (i.e. 400, 900, 1200, 1800,

or 2400).

Perfect! Two questions:

What’s the difference between MIMO-B and MIMO-A?

I assume burning the eeprom is undo-able (redo-able, I suppose)?

Thanks,

-Dan


#4

Dan H. wrote:

Put the RFX on a USRP (side A) and run the following:

I assume burning the eeprom is undo-able (redo-able, I suppose)?

MIMO_B uses the 64 MHz oscillator from the motherboard (only on the
newer ones), and is cleaner. MIMO_A uses an FPGA pin as a clock so it
isn’t as clean.

Matt


#5

Matt E. wrote:

MIMO_B uses the 64 MHz oscillator from the motherboard (only on the
newer ones), and is cleaner. MIMO_A uses an FPGA pin as a clock so it
isn’t as clean.

Does this apply to DBSRX as well?

Thanks,

Chris


#6

Chris S. wrote:

Matt E. wrote:

MIMO_B uses the 64 MHz oscillator from the motherboard (only on the
newer ones), and is cleaner. MIMO_A uses an FPGA pin as a clock so it
isn’t as clean.

Does this apply to DBSRX as well?

Sort of. The DBSRX does operate essentially in the MIMO_A mode, but the
cleanliness of the reference is not as big a concern due to the much
narrower loop bandwidth of its PLL.

Matt


#7

I assume burning the eeprom is undo-able (redo-able, I suppose)?

Yep. EEPROM = Electrically Erasable Programmable ROM


#8

Hi

I’m using an RFX400 with my revision 3 USRP.

After digging through the archive I found that I needed to modify the
RFX400
and then update its EEPROM as described here:

On Thu, Feb 8, 2007 at 10:18 AM, Matt E. removed_email_address@domain.invalid wrote:

  usrp/host/apps/burn-db-eeprom -f -A -t rfxYYYY_mimo_a

       where YYYY is the board you have (i.e. 400, 900, 1200, 1800,

or 2400).

The hardware mods are made but I get an error when I try and set the
daughterboard type using “burn-db-eeprom -f -A -t rfx400_mimo_a” and it
says
this:

Traceback (most recent call last):
File “usrp/host/apps/burn-db-eeprom”, line 69, in
‘xcvr2450’ : ((XCVR2450_TX, 0x0000), (XCVR2450_RX,
0x0000)),
NameError: name ‘XCVR2450_TX’ is not defined

usrp_print_db.py gives me the following so I am sure side A is the right
side A :wink:

RX d’board A: Flex 400 Rx MIMO B
RX d’board B: TV Rx
TX d’board A: Flex 400 Tx MIMO B
TX d’board B:

Any clues?

Steve


#9

Oops!

I did nothing other than run the wfm receiver and tried again. It
worked!

Steve