X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/6658905f18a1eebc148836f26c731dea9c1377dc..e481bc32992b13b6fbbc31dffa9a8d63b393a952:/fpga/lo_simulate.v

diff --git a/fpga/lo_simulate.v b/fpga/lo_simulate.v
index 7eb910ba..57e602a2 100644
--- a/fpga/lo_simulate.v
+++ b/fpga/lo_simulate.v
@@ -1,37 +1,83 @@
-//-----------------------------------------------------------------------------
-// The way that we connect things in low-frequency simulation mode. In this
-// case just pass everything through to the ARM, which can bit-bang this
-// (because it is so slow).
-//
-// Jonathan Westhues, April 2006
-//-----------------------------------------------------------------------------
-
-module lo_simulate(
-    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 = ssp_dout;
-assign pwr_oe2 = ssp_dout;
-assign pwr_oe4 = ssp_dout;
-assign ssp_clk = cross_lo;
-assign pwr_lo = 1'b0;
-assign adc_clk = 1'b0;
-assign pwr_hi = 1'b0;
-assign dbg = cross_lo;
-
-endmodule
+//-----------------------------------------------------------------------------
+// The way that we connect things in low-frequency simulation mode. In this
+// case just pass everything through to the ARM, which can bit-bang this
+// (because it is so slow).
+//
+// Jonathan Westhues, April 2006
+//-----------------------------------------------------------------------------
+
+module lo_simulate(
+    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,
+	 divisor
+);
+    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;
+	 input [7:0] divisor;
+
+// No logic, straight through.
+assign pwr_oe3 = 1'b0;
+assign pwr_oe1 = ssp_dout;
+assign pwr_oe2 = ssp_dout;
+assign pwr_oe4 = ssp_dout;
+assign ssp_clk = cross_lo;
+assign pwr_lo = 1'b0;
+assign pwr_hi = 1'b0;
+assign dbg = ssp_frame;
+
+// Divide the clock to be used for the ADC
+reg [7:0] pck_divider;
+reg clk_state;
+
+always @(posedge pck0)
+begin
+	if(pck_divider == divisor[7:0])
+		begin
+			pck_divider <= 8'd0;
+			clk_state = !clk_state;
+		end
+	else
+	begin
+		pck_divider <= pck_divider + 1;
+	end
+end
+
+assign adc_clk = ~clk_state;
+
+// Toggle the output with hysteresis
+//  Set to high if the ADC value is above 200
+//  Set to low if the ADC value is below 64
+reg is_high;
+reg is_low;
+reg output_state;
+
+always @(posedge pck0)
+begin
+	if((pck_divider == 8'd7) && !clk_state) begin
+		is_high = (adc_d >= 8'd200);
+		is_low = (adc_d <= 8'd64);
+	end
+end
+
+always @(posedge is_high or posedge is_low)
+begin
+	if(is_high)
+		output_state <= 1'd1;
+	else if(is_low)
+		output_state <= 1'd0;
+end
+
+assign ssp_frame = output_state;
+
+endmodule
+