Re: [Discuss-gnuradio] A rfx2400 is down, which chip on the borad is broken?

[Lin HUANG]

I'd like to report to all of you our investigation results. At least, the TX side works now. But for the RX side, I think it is absolutely broken and I give up to repair it.

I changed the resistors R40, R42, R46, R130, R132, R136 to be 1k ohms. This prevents the RX side influencing the TX side. And I connected the 6V power of TX side with the power pin of the control part (U203), because the power of RX is not normal. Then the TX side can work.
 

Thanks a lot for Ettus's help.~ 

HUANG Lin 

 

2007/5/30, Lin HUANG <address@hidden>:

I continued checking these broken boards recent days. I found for the TX side, the graph stops as soon as it starts. It seems the daughter board gives some signal to stop the motherboard to load data from PC. I read the .sch file in the subversion repository and the defination of the interface between db and mb.

 

IOUTN_B IOUTP_B IOUTP_A IOUTN_A   ---- the analog IF signal   mb-->db

clock ---- the db is synchronous with mb   mb-->db

I2C_A0 I2C_A1 ---- TX/RX RX1/RX switch control signal  mb-->db

SCLK SDA ---- R/W interface to E2PROM  mb<-->db

IO0~IO15 ---- for debug usage. mb<-->db

 

Which pin will give a wrong signal to motherboard and disable the board? IO? We never used u_write_oe. So it may be as a input?

 

Thanks for Eric and Nikhil's help before. Hope you are continously interested in my bug investigation. Thank you. :)

HUANG Lin