fixing iso14443b (issue #103):

- revert removal of FPGA_HF_READER_RX_XCORR_848_KHZ. Need to be able to switch to 424kHz for ISO15693.
This commit is contained in:
pwpiwi 2015-06-18 15:30:56 +02:00
commit da586b1702
4 changed files with 26 additions and 10 deletions

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@ -67,8 +67,10 @@ assign major_mode = conf_word[7:5];
// some fraction of the buffers)
wire hi_read_tx_shallow_modulation = conf_word[0];
// For the high-frequency receive correlator:
// whether to drive the coil (reader) or just short it (snooper)
// For the high-frequency receive correlator: frequency against which to
// correlate.
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];
// For the high-frequency simulated tag: what kind of modulation to use.
@ -97,7 +99,7 @@ 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_snoop
hi_read_rx_xcorr_848, hi_read_rx_xcorr_snoop
);
hi_simulate hs(

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@ -10,7 +10,7 @@ module hi_read_rx_xcorr(
ssp_frame, ssp_din, ssp_dout, ssp_clk,
cross_hi, cross_lo,
dbg,
snoop
xcorr_is_848, snoop
);
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 snoop;
input xcorr_is_848, snoop;
// Carrier is steady on through this, unless we're snooping.
assign pwr_hi = ck_1356megb & (~snoop);
@ -28,8 +28,22 @@ assign pwr_oe1 = 1'b0;
assign pwr_oe3 = 1'b0;
assign pwr_oe4 = 1'b0;
wire adc_clk = ck_1356megb;
(* clock_signal = "yes" *) reg fc_div_2;
always @(negedge ck_1356megb)
fc_div_2 <= fc_div_2 + 1;
(* clock_signal = "yes" *) reg adc_clk;
always @(xcorr_is_848, ck_1356megb, fc_div_2)
if (xcorr_is_848)
// The subcarrier frequency is fc/16; we will sample at fc, so that
// means the subcarrier is 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 ...
adc_clk <= ck_1356megb;
else
// The subcarrier frequency is fc/32; we will sample at fc/2, and
// the subcarrier will look identical.
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.