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|
`timescale 1ns / 1ps
module novena_baseline_top
(
gclk_p_pin, gclk_n_pin,
eim_bclk, eim_cs0_n, eim_da,
eim_lba_n, eim_wr_n,
eim_oe_n, eim_wait_n,
reset_mcu_b_pin,
apoptosis_pin,
led_pin
);
//
// Top-Levl Ports
//
input wire gclk_p_pin; // general-purpose 50 MHz LVDS clock
input wire gclk_n_pin; //
input wire eim_bclk; // burst clock from cpu
input wire eim_cs0_n; // chip select (active low)
inout wire [15: 0] eim_da; // bi-directional address/data bus
input wire eim_lba_n; // latch address signal (active low)
input wire eim_wr_n; // write enable signal (active low)
input wire eim_oe_n; // output enable signal (active low)
output wire eim_wait_n; // wait signal (active low)
input wire reset_mcu_b_pin; // this must be configured as input w/pullup
// not to kill the cpu after configuration
output wire apoptosis_pin; // not used, tied to 0
output wire led_pin; // visual activity indicator
//
// Clock Manager
//
/* Clock manager is used to buffer BCLK and also generate SYS_CLK from GCLK. */
wire sys_clk;
wire sys_rst;
wire eim_bclk_buf;
novena_clkmgr clkmgr
(
.gclk_p (gclk_p_pin),
.gclk_n (gclk_n_pin),
.reset_mcu_b (reset_mcu_b_pin),
.sys_clk (sys_clk),
.sys_rst (sys_rst),
.bclk_in (eim_bclk),
.bclk_out (eim_bclk_buf)
);
//
// EIM Arbiter
//
/* EIM arbiter handles EIM access and transfers it into `sys_clk' clock domain. */
wire [13: 0] sys_eim_addr;
wire sys_eim_wr;
wire sys_eim_rd;
wire [31: 0] sys_eim_dout;
wire [31: 0] sys_eim_din;
eim_arbiter eim
(
.eim_bclk (eim_bclk_buf),
.eim_cs0_n (eim_cs0_n),
.eim_da (eim_da),
.eim_lba_n (eim_lba_n),
.eim_wr_n (eim_wr_n),
.eim_oe_n (eim_oe_n),
.eim_wait_n (eim_wait_n),
.sys_clk (sys_clk),
.sys_addr (sys_eim_addr),
.sys_wren (sys_eim_wr),
.sys_data_out (sys_eim_dout),
.sys_rden (sys_eim_rd),
.sys_data_in (sys_eim_din)
);
//
// Core Selector (MUX)
//
/* This multiplexor is used to map demo adder registers somewhere into EIM address space. */
core_selector mux
(
.sys_clk (sys_clk),
.sys_rst (sys_rst),
.sys_eim_addr (sys_eim_addr),
.sys_eim_wr (sys_eim_wr),
.sys_eim_rd (sys_eim_rd),
.sys_eim_dout (sys_eim_dout),
.sys_eim_din (sys_eim_din)
);
//
// LED Driver
//
eim_indicator led
(
.sys_clk (sys_clk),
.sys_rst (sys_rst),
.eim_active (sys_eim_wr | sys_eim_rd),
.led_out (led_pin)
);
//
// Unused
//
assign apoptosis_pin = 1'b0;
endmodule
|
