On 05/21/2010 06:33 AM, Harley Myler wrote:
I traced those from the WBX simple GDB, through the WBX and to the USRP2. They wind-up at U1 (XC3SXX00FG456−IO7(tx)) and U1 (XC3SXX00FG456−IO2(rx)) on page 3 of 8 of the USRP2 schematic. I do not know why they are both labelled "U1". The date, revision and drawn-by blocks only had tokens. I may be looking at a preliminary schematic.
It's a 456 pin part, which would be huge if it wasn't split up. The actual part number is XC3S2000-5FGG456. The XX in the part name in the schematic is because the 1000, 1500, and 2000 are all pin compatible.
So at this juncture my assumption is that the FPGA(s) given by the XC... labels above, although I cannot find a Xylinx part number match, simply run out to the 20 pin header connector on the daughterboard. Of the sixteen lines, each daughterboard usurps--an ironic term here--any number of the available 16 GPIOs for their own purposes and what is left are available to the user.
Yes.
As such, my conclusion is that the following, per the schematic, are available: RX Control Pins io_rx[15:14] −− Unused TX Control Pins iotx[15:8] −− Unused
IO_RX[15] RX antenna selector pin IO_RX[14] Available IO_RX[13:8] RX attenuator control IO_RX[7] RX 5V supply enable IO_RX[6] RX 3.3V supply enable IO_RX[5] Available IO_RX[4] RX baseband amp enable IO_RX[3] RX PLL Chip enable IO_RX[2] RX PLL power down IO_RX[1] RX PLL mux for debug IO_RX[0] RX PLL lock detect IO_TX[15] TX/RX switch IO_TX[14] Available IO_TX[13] Available IO_TX[12] Available IO_TX[11] Available IO_TX[10] Available IO_TX[9] Available IO_TX[8] Available IO_TX[7] TX 5V supply enable IO_TX[6] TX 3.3V supply enable IO_TX[5] Available IO_TX[4] TX mixer enable IO_TX[3] TX PLL chip enable IO_TX[2] TX PLL power down IO_TX[1] TX PLL mux for debug IO_TX[0] TX PLL lock detect
This gives 9 GPIO pins available to the user, hardly 16. The product documentation should reflect this. Nevertheless, nine will be adequate for my purposes.
I count 10 in the above list. The WBX docs never say there are 16 pins, as far as I can tell. It is the USRP and USRP2 documentation which states 16 pins are available, and they are.
Matt _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
