-//-----------------------------------------------------------------------------
-// The FPGA is responsible for interfacing between the A/D, the coil drivers,
-// and the ARM. In the low-frequency modes it passes the data straight
-// through, so that the ARM gets raw A/D samples over the SSP. In the high-
-// frequency modes, the FPGA might perform some demodulation first, to
-// reduce the amount of data that we must send to the ARM.
-//
-// I am not really an FPGA/ASIC designer, so I am sure that a lot of this
-// could be improved.
-//
-// Jonathan Westhues, March 2006
-// Added ISO14443-A support by Gerhard de Koning Gans, April 2008
-//-----------------------------------------------------------------------------
-
-`include "lo_read.v"
-`include "lo_passthru.v"
-`include "lo_edge_detect.v"
-`include "hi_read_tx.v"
-`include "hi_read_rx_xcorr.v"
-`include "hi_simulate.v"
-`include "hi_iso14443a.v"
-`include "util.v"
-
-module fpga(
- spck, miso, mosi, ncs,
- pck0, ck_1356meg, ck_1356megb,
- pwr_lo, pwr_hi, pwr_oe1, pwr_oe2, pwr_oe3, pwr_oe4,
- adc_d, adc_clk, adc_noe,
- ssp_frame, ssp_din, ssp_dout, ssp_clk,
- cross_hi, cross_lo,
- dbg
-);
- input spck, mosi, ncs;
- output miso;
- 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, adc_noe;
- input ssp_dout;
- output ssp_frame, ssp_din, ssp_clk;
- input cross_hi, cross_lo;
- output dbg;
-
-//assign pck0 = pck0i;
-// IBUFG #(.IOSTANDARD("DEFAULT") ) pck0b(
-// .O(pck0),
-// .I(pck0i)
-// );
-//assign spck = spcki;
-// IBUFG #(.IOSTANDARD("DEFAULT") ) spckb(
- // .O(spck),
- // .I(spcki)
-// );
-
-
-//-----------------------------------------------------------------------------
-// The SPI receiver. This sets up the configuration word, which the rest of
-// the logic looks at to determine how to connect the A/D and the coil
-// drivers (i.e., which section gets it). Also assign some symbolic names
-// to the configuration bits, for use below.
-//-----------------------------------------------------------------------------
-
-reg [15:0] shift_reg;
-reg [7:0] divisor;
-reg [7:0] conf_word;
-
-// We switch modes between transmitting to the 13.56 MHz tag and receiving
-// from it, which means that we must make sure that we can do so without
-// glitching, or else we will glitch the transmitted carrier.
-always @(posedge ncs)
-begin
- case(shift_reg[15:12])
- 4'b0001: conf_word <= shift_reg[7:0]; // FPGA_CMD_SET_CONFREG
- 4'b0010: divisor <= shift_reg[7:0]; // FPGA_CMD_SET_DIVISOR
- endcase
-end
-
-always @(posedge spck)
-begin
- if(~ncs)
- begin
- shift_reg[15:1] <= shift_reg[14:0];
- shift_reg[0] <= mosi;
- end
-end
-
-wire [2:0] major_mode;
-assign major_mode = conf_word[7:5];
-
-// For the low-frequency configuration:
-wire lo_is_125khz;
-assign lo_is_125khz = conf_word[3];
-
-// For the high-frequency transmit configuration: modulation depth, either
-// 100% (just quite driving antenna, steady LOW), or shallower (tri-state
-// some fraction of the buffers)
-wire hi_read_tx_shallow_modulation;
-assign hi_read_tx_shallow_modulation = conf_word[0];
-
-// For the high-frequency receive correlator: frequency against which to
-// correlate.
-wire hi_read_rx_xcorr_848;
-assign 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;
-assign hi_read_rx_xcorr_snoop = conf_word[1];
-
-// Divide the expected subcarrier frequency for hi_read_rx_xcorr by 4
-wire hi_read_rx_xcorr_quarter;
-assign 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;
-assign hi_simulate_mod_type = conf_word[2:0];
-
-// For the high-frequency simulated tag: what kind of modulation to use.
-wire lf_field;
-assign lf_field = conf_word[0];
-
-//-----------------------------------------------------------------------------
-// And then we instantiate the modules corresponding to each of the FPGA's
-// major modes, and use muxes to connect the outputs of the active mode to
-// the output pins.
-//-----------------------------------------------------------------------------
-
-lo_read lr(
- pck0, ck_1356meg, ck_1356megb,
- lr_pwr_lo, lr_pwr_hi, lr_pwr_oe1, lr_pwr_oe2, lr_pwr_oe3, lr_pwr_oe4,
- adc_d, lr_adc_clk,
- lr_ssp_frame, lr_ssp_din, ssp_dout, lr_ssp_clk,
- cross_hi, cross_lo,
- lr_dbg,
- lo_is_125khz, divisor
-);
-
-lo_passthru lp(
- pck0, ck_1356meg, ck_1356megb,
- lp_pwr_lo, lp_pwr_hi, lp_pwr_oe1, lp_pwr_oe2, lp_pwr_oe3, lp_pwr_oe4,
- adc_d, lp_adc_clk,
- lp_ssp_frame, lp_ssp_din, ssp_dout, lp_ssp_clk,
- cross_hi, cross_lo,
- lp_dbg, divisor
-);
-
-lo_edge_detect ls(
- pck0, ck_1356meg, ck_1356megb,
- ls_pwr_lo, ls_pwr_hi, ls_pwr_oe1, ls_pwr_oe2, ls_pwr_oe3, ls_pwr_oe4,
- adc_d, ls_adc_clk,
- ls_ssp_frame, ls_ssp_din, ssp_dout, ls_ssp_clk,
- cross_hi, cross_lo,
- ls_dbg, divisor,
- lf_field
-);
-
-hi_read_tx ht(
- pck0, ck_1356meg, ck_1356megb,
- ht_pwr_lo, ht_pwr_hi, ht_pwr_oe1, ht_pwr_oe2, ht_pwr_oe3, ht_pwr_oe4,
- adc_d, ht_adc_clk,
- ht_ssp_frame, ht_ssp_din, ssp_dout, ht_ssp_clk,
- cross_hi, cross_lo,
- ht_dbg,
- hi_read_tx_shallow_modulation
-);
-
-hi_read_rx_xcorr hrxc(
- pck0, ck_1356meg, ck_1356megb,
- hrxc_pwr_lo, hrxc_pwr_hi, hrxc_pwr_oe1, hrxc_pwr_oe2, hrxc_pwr_oe3, hrxc_pwr_oe4,
- adc_d, hrxc_adc_clk,
- 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_quarter
-);
-
-hi_simulate hs(
- pck0, ck_1356meg, ck_1356megb,
- hs_pwr_lo, hs_pwr_hi, hs_pwr_oe1, hs_pwr_oe2, hs_pwr_oe3, hs_pwr_oe4,
- adc_d, hs_adc_clk,
- hs_ssp_frame, hs_ssp_din, ssp_dout, hs_ssp_clk,
- cross_hi, cross_lo,
- hs_dbg,
- hi_simulate_mod_type
-);
-
-hi_iso14443a hisn(
- pck0, ck_1356meg, ck_1356megb,
- hisn_pwr_lo, hisn_pwr_hi, hisn_pwr_oe1, hisn_pwr_oe2, hisn_pwr_oe3, hisn_pwr_oe4,
- adc_d, hisn_adc_clk,
- hisn_ssp_frame, hisn_ssp_din, ssp_dout, hisn_ssp_clk,
- cross_hi, cross_lo,
- hisn_dbg,
- hi_simulate_mod_type
-);
-
-// Major modes:
-// 000 -- LF reader (generic)
-// 001 -- LF simulated tag (generic)
-// 010 -- HF reader, transmitting to tag; modulation depth selectable
-// 011 -- HF reader, receiving from tag, correlating as it goes; frequency selectable
-// 100 -- HF simulated tag
-// 101 -- HF ISO14443-A
-// 110 -- LF passthrough
-// 111 -- everything off
-
-mux8 mux_ssp_clk (major_mode, ssp_clk, lr_ssp_clk, ls_ssp_clk, ht_ssp_clk, hrxc_ssp_clk, hs_ssp_clk, hisn_ssp_clk, lp_ssp_clk, 1'b0);
-mux8 mux_ssp_din (major_mode, ssp_din, lr_ssp_din, ls_ssp_din, ht_ssp_din, hrxc_ssp_din, hs_ssp_din, hisn_ssp_din, lp_ssp_din, 1'b0);
-mux8 mux_ssp_frame (major_mode, ssp_frame, lr_ssp_frame, ls_ssp_frame, ht_ssp_frame, hrxc_ssp_frame, hs_ssp_frame, hisn_ssp_frame, lp_ssp_frame, 1'b0);
-mux8 mux_pwr_oe1 (major_mode, pwr_oe1, lr_pwr_oe1, ls_pwr_oe1, ht_pwr_oe1, hrxc_pwr_oe1, hs_pwr_oe1, hisn_pwr_oe1, lp_pwr_oe1, 1'b0);
-mux8 mux_pwr_oe2 (major_mode, pwr_oe2, lr_pwr_oe2, ls_pwr_oe2, ht_pwr_oe2, hrxc_pwr_oe2, hs_pwr_oe2, hisn_pwr_oe2, lp_pwr_oe2, 1'b0);
-mux8 mux_pwr_oe3 (major_mode, pwr_oe3, lr_pwr_oe3, ls_pwr_oe3, ht_pwr_oe3, hrxc_pwr_oe3, hs_pwr_oe3, hisn_pwr_oe3, lp_pwr_oe3, 1'b0);
-mux8 mux_pwr_oe4 (major_mode, pwr_oe4, lr_pwr_oe4, ls_pwr_oe4, ht_pwr_oe4, hrxc_pwr_oe4, hs_pwr_oe4, hisn_pwr_oe4, lp_pwr_oe4, 1'b0);
-mux8 mux_pwr_lo (major_mode, pwr_lo, lr_pwr_lo, ls_pwr_lo, ht_pwr_lo, hrxc_pwr_lo, hs_pwr_lo, hisn_pwr_lo, lp_pwr_lo, 1'b0);
-mux8 mux_pwr_hi (major_mode, pwr_hi, lr_pwr_hi, ls_pwr_hi, ht_pwr_hi, hrxc_pwr_hi, hs_pwr_hi, hisn_pwr_hi, lp_pwr_hi, 1'b0);
-mux8 mux_adc_clk (major_mode, adc_clk, lr_adc_clk, ls_adc_clk, ht_adc_clk, hrxc_adc_clk, hs_adc_clk, hisn_adc_clk, lp_adc_clk, 1'b0);
-mux8 mux_dbg (major_mode, dbg, lr_dbg, ls_dbg, ht_dbg, hrxc_dbg, hs_dbg, hisn_dbg, lp_dbg, 1'b0);
-
-// In all modes, let the ADC's outputs be enabled.
-assign adc_noe = 1'b0;
-
-endmodule