github/proxmark3
1
0
Fork 0
mirror of https://github.com/Proxmark/proxmark3.git synced 2025-07-06 13:11:18 -07:00
Code Issues Projects Releases Packages Wiki Activity Actions

revert removal of quarter frequency support for hi_read_rx_xcorr.v

Browse source
This commit is contained in:
pwpiwi 2017-07-11 08:50:27 +02:00
parent 067bfc8b76
commit 3f7aaf24fb
4 changed files with 20 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

1
armsrc/fpgaloader.h
View file

@ -58,6 +58,7 @@ void SetAdcMuxFor(uint32_t whichGpio);
// Options for the HF reader, correlating against rx from tag
#define FPGA_HF_READER_RX_XCORR_848_KHZ (1<<0)
#define FPGA_HF_READER_RX_XCORR_SNOOP (1<<1)
#define FPGA_HF_READER_RX_XCORR_QUARTER_FREQ (1<<2)
// Options for the HF simulated tag, how to modulate
#define FPGA_HF_SIMULATOR_NO_MODULATION (0<<0)
#define FPGA_HF_SIMULATOR_MODULATE_BPSK (1<<0)

BIN
fpga/fpga_hf.bit
View file

Binary file not shown.

4
fpga/fpga_hf.v
View file

@ -73,6 +73,8 @@ wire hi_read_tx_shallow_modulation = conf_word[0];
wire hi_read_rx_xcorr_848 = conf_word[0];
// and whether to drive the coil (reader) or just short it (snooper)
wire hi_read_rx_xcorr_snoop = conf_word[1];
// divide subcarrier frequency by 4
wire hi_read_rx_xcorr_quarter = conf_word[2];
// For the high-frequency simulated tag: what kind of modulation to use.
wire [2:0] hi_simulate_mod_type = conf_word[2:0];
@ -100,7 +102,7 @@ hi_read_rx_xcorr hrxc(
hrxc_ssp_frame, hrxc_ssp_din, ssp_dout, hrxc_ssp_clk,
cross_hi, cross_lo,
hrxc_dbg,
hi_read_rx_xcorr_848, hi_read_rx_xcorr_snoop
hi_read_rx_xcorr_848, hi_read_rx_xcorr_snoop, hi_read_rx_xcorr_quarter
);
hi_simulate hs(

31
fpga/hi_read_rx_xcorr.v
View file

@ -10,7 +10,7 @@ module hi_read_rx_xcorr(
ssp_frame, ssp_din, ssp_dout, ssp_clk,
cross_hi, cross_lo,
dbg,
xcorr_is_848, snoop
xcorr_is_848, snoop, xcorr_quarter_freq
);
input pck0, ck_1356meg, ck_1356megb;
output pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4;
@ -20,7 +20,7 @@ module hi_read_rx_xcorr(
output ssp_frame, ssp_din, ssp_clk;
input cross_hi, cross_lo;
output dbg;
input xcorr_is_848, snoop;
input xcorr_is_848, snoop, xcorr_quarter_freq;
// Carrier is steady on through this, unless we're snooping.
assign pwr_hi = ck_1356megb & (~snoop);
@ -28,19 +28,21 @@ assign pwr_oe1 = 1'b0;
assign pwr_oe3 = 1'b0;
assign pwr_oe4 = 1'b0;
// Clock divider
reg [0:0] fc_divider;
reg [2:0] fc_div;
always @(negedge ck_1356megb)
fc_divider <= fc_divider + 1;
wire fc_div2 = fc_divider[0];
fc_div <= fc_div + 1;
reg adc_clk;
always @(ck_1356megb)
if (xcorr_is_848)
(* clock_signal = "yes" *) reg adc_clk; // sample frequency, always 16 * fc
always @(ck_1356megb, xcorr_is_848, xcorr_quarter_freq, fc_div)
if (xcorr_is_848 & ~xcorr_quarter_freq) // fc = 847.5 kHz
adc_clk <= ck_1356megb;
else
adc_clk <= fc_div2;
else if (~xcorr_is_848 & ~xcorr_quarter_freq) // fc = 424.25 kHz
adc_clk <= fc_div[0];
else if (xcorr_is_848 & xcorr_quarter_freq) // fc = 212.125 kHz
adc_clk <= fc_div[1];
else // fc = 106.0625 kHz
adc_clk <= fc_div[2];
// When we're a reader, we just need to do the BPSK demod; but when we're an
// eavesdropper, we also need to pick out the commands sent by the reader,
// using AM. Do this the same way that we do it for the simulated tag.
@ -71,8 +73,7 @@ end
// so we need a 6-bit counter.
reg [5:0] corr_i_cnt;
// And a couple of registers in which to accumulate the correlations.
// we would add at most 32 times adc_d, the result can be held in 13 bits.
// Need one additional bit because it can be negative as well
// we would add/sub at most 32 times adc_d, the signed result can be held in 14 bits.
reg signed [13:0] corr_i_accum;
reg signed [13:0] corr_q_accum;
reg signed [7:0] corr_i_out;
@ -84,7 +85,7 @@ reg ssp_frame;
always @(negedge adc_clk)
begin
corr_i_cnt <= corr_i_cnt + 1;
corr_i_cnt <= corr_i_cnt + 1;
end