Added FPGA passthrough mode for TI tags

fpga/lo_passthru.v

@@ -0,0 +1,35 @@
+//-----------------------------------------------------------------------------
+// For reading TI tags, we need to place the FPGA in pass through mode
+// and pass everything through to the ARM
+//-----------------------------------------------------------------------------
+
+module lo_passthru(
+    pck0, ck_1356meg, ck_1356megb,
+    pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4,
+    adc_d, adc_clk,
+    ssp_frame, ssp_din, ssp_dout, ssp_clk,
+    cross_hi, cross_lo,
+    dbg
+);
+    input pck0, ck_1356meg, ck_1356megb;
+    output pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4;
+    input [7:0] adc_d;
+    output adc_clk;
+    input ssp_dout;
+    output ssp_frame, ssp_din, ssp_clk;
+    input cross_hi, cross_lo;
+    output dbg;
+
+// No logic, straight through.
+
+assign pwr_oe3 = 1'b0;
+assign pwr_oe1 = 1'b1;
+assign pwr_oe2 = 1'b1;
+assign pwr_oe4 = 1'b1;
+assign pwr_lo = 1'b0;
+assign pwr_hi = 1'b0;
+assign adc_clk = 1'b0;
+assign ssp_din = cross_lo;
+assign dbg = cross_lo;
+
+endmodule