(implementing suggestion #94)

[proxmark3-svn] / fpga / lo_passthru.v

diff --git a/fpga/lo_passthru.v b/fpga/lo_passthru.v
index e1cb2ef23f4527a72997fbf4949a7bca523e6989..3507f660ed69498d3dc671dff71f8a14fd672eff 100644 (file)
--- a/fpga/lo_passthru.v
+++ b/fpga/lo_passthru.v
@@ -1,56 +1,29 @@
-//-----------------------------------------------------------------------------\r
-// For reading TI tags, we need to place the FPGA in pass through mode\r
-// and pass everything through to the ARM\r
-//-----------------------------------------------------------------------------\r
-\r
-module lo_passthru(\r
-    pck0, ck_1356meg, ck_1356megb,\r
-    pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4,\r
-    adc_d, adc_clk,\r
-    ssp_frame, ssp_din, ssp_dout, ssp_clk,\r
-    cross_hi, cross_lo,\r
-    dbg, divisor\r
-);\r
-    input pck0, ck_1356meg, ck_1356megb;\r
-    output pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4;\r
-    input [7:0] adc_d;\r
-    output adc_clk;\r
-    input ssp_dout;\r
-    output ssp_frame, ssp_din, ssp_clk;\r
-    input cross_hi, cross_lo;\r
-    output dbg;\r
-    input [7:0] divisor;\r
-\r
-reg [7:0] pck_divider;\r
-reg ant_lo;\r
-\r
-// this task runs on the rising egde of pck0 clock (24Mhz) and creates ant_lo\r
-// which is high for (divisor+1) pck0 cycles and low for the same duration\r
-// ant_lo is therefore a 50% duty cycle clock signal with a frequency of\r
-// 12Mhz/(divisor+1) which drives the antenna as well as the ADC clock adc_clk\r
-always @(posedge pck0)\r
-begin\r
-       if(pck_divider == divisor[7:0])\r
-               begin\r
-                       pck_divider <= 8'd0;\r
-                       ant_lo = !ant_lo;\r
-               end\r
-       else\r
-       begin\r
-               pck_divider <= pck_divider + 1;\r
-       end\r
-end\r
-\r
-// the antenna is modulated when ssp_dout = 1, when 0 the\r
-// antenna drivers stop modulating and go into listen mode\r
-assign pwr_oe3 = 1'b0;\r
-assign pwr_oe1 = ssp_dout;\r
-assign pwr_oe2 = ssp_dout;\r
-assign pwr_oe4 = ssp_dout;\r
-assign pwr_lo = ant_lo && ssp_dout;\r
-assign pwr_hi = 1'b0;\r
-assign adc_clk = 1'b0;\r
-assign ssp_din = cross_lo;\r
-assign dbg = cross_lo;\r
-\r
-endmodule\r
+//-----------------------------------------------------------------------------
+// For reading TI tags, we need to place the FPGA in pass through mode
+// and pass everything through to the ARM
+//-----------------------------------------------------------------------------
+// iZsh <izsh at fail0verflow.com>, June 2014
+
+module lo_passthru(
+       input pck_divclk,
+       output pwr_lo, output pwr_hi,
+       output pwr_oe1, output pwr_oe2, output pwr_oe3, output pwr_oe4,
+       output adc_clk,
+       output ssp_din, input ssp_dout,
+       input cross_lo,
+       output dbg
+);
+
+// the antenna is modulated when ssp_dout = 1, when 0 the
+// antenna drivers stop modulating and go into listen mode
+assign pwr_oe3 = 1'b0;
+assign pwr_oe1 = ssp_dout;
+assign pwr_oe2 = ssp_dout;
+assign pwr_oe4 = ssp_dout;
+assign pwr_lo = pck_divclk && ssp_dout;
+assign pwr_hi = 1'b0;
+assign adc_clk = 1'b0;
+assign ssp_din = cross_lo;
+assign dbg = cross_lo;
+
+endmodule