X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/5ea2a24839c71ba6e58af937a392a6204b8b4696..a66f26da182040ac798a7c629d255cb86803e9c2:/fpga/hi_simulate.v?ds=sidebyside diff --git a/fpga/hi_simulate.v b/fpga/hi_simulate.v index de58a74e..92ebcb51 100644 --- a/fpga/hi_simulate.v +++ b/fpga/hi_simulate.v @@ -47,46 +47,48 @@ end // Divide 13.56 MHz to produce various frequencies for SSP_CLK // and modulation. -reg [7:0] ssp_clk_divider; +reg [8:0] ssp_clk_divider; -always @(posedge adc_clk) +always @(negedge adc_clk) ssp_clk_divider <= (ssp_clk_divider + 1); reg ssp_clk; always @(negedge adc_clk) begin - if(mod_type == `FPGA_HF_SIMULATOR_MODULATE_424K_8BIT) + if (mod_type == `FPGA_HF_SIMULATOR_MODULATE_424K_8BIT) // Get bit every at 53KHz (every 8th carrier bit of 424kHz) - ssp_clk <= ssp_clk_divider[7]; - else if(mod_type == `FPGA_HF_SIMULATOR_MODULATE_212K) + ssp_clk <= ~ssp_clk_divider[7]; + else if (mod_type == `FPGA_HF_SIMULATOR_MODULATE_212K) // Get next bit at 212kHz - ssp_clk <= ssp_clk_divider[5]; + ssp_clk <= ~ssp_clk_divider[5]; else // Get next bit at 424Khz - ssp_clk <= ssp_clk_divider[4]; + ssp_clk <= ~ssp_clk_divider[4]; end -// Divide SSP_CLK by 8 to produce the byte framing signal; the phase of -// this is arbitrary, because it's just a bitstream. -// One nasty issue, though: I can't make it work with both rx and tx at -// once. The phase wrt ssp_clk must be changed. TODO to find out why -// that is and make a better fix. -reg [2:0] ssp_frame_divider_to_arm; -always @(posedge ssp_clk) - ssp_frame_divider_to_arm <= (ssp_frame_divider_to_arm + 1); -reg [2:0] ssp_frame_divider_from_arm; -always @(negedge ssp_clk) - ssp_frame_divider_from_arm <= (ssp_frame_divider_from_arm + 1); - - +// Produce the byte framing signal; the phase of this signal +// is arbitrary, because it's just a bit stream in this module. reg ssp_frame; -always @(ssp_frame_divider_to_arm or ssp_frame_divider_from_arm or mod_type) - if(mod_type == `FPGA_HF_SIMULATOR_NO_MODULATION) // not modulating, so listening, to ARM - ssp_frame = (ssp_frame_divider_to_arm == 3'b000); - else - ssp_frame = (ssp_frame_divider_from_arm == 3'b000); +always @(negedge adc_clk) +begin + if (mod_type == `FPGA_HF_SIMULATOR_MODULATE_212K) + begin + if (ssp_clk_divider[8:5] == 4'd1) + ssp_frame <= 1'b1; + if (ssp_clk_divider[8:5] == 4'd5) + ssp_frame <= 1'b0; + end + else + begin + if (ssp_clk_divider[7:4] == 4'd1) + ssp_frame <= 1'b1; + if (ssp_clk_divider[7:4] == 4'd5) + ssp_frame <= 1'b0; + end +end + // Synchronize up the after-hysteresis signal, to produce DIN. reg ssp_din; @@ -120,6 +122,6 @@ assign pwr_lo = 1'b0; assign pwr_oe2 = 1'b0; -assign dbg = ssp_din; +assign dbg = ssp_frame; endmodule