From 1d97a0955e863b7dc7bbe4350bcef8c2047768d8 Mon Sep 17 00:00:00 2001
From: Joshua Wise <joshua@rebirth.joshuawise.com>
Date: Fri, 9 Jan 2009 01:19:12 -0500
Subject: [PATCH] Add terminal

---
 Terminal.v    | 33 +++++++++++++++++++++++++++++++++
 system.v      | 17 ++++++++++++++---
 testbench.cpp | 22 ++++++++++++++++++++++
 3 files changed, 69 insertions(+), 3 deletions(-)
 create mode 100644 Terminal.v

diff --git a/Terminal.v b/Terminal.v
new file mode 100644
index 0000000..9dc5a21
--- /dev/null
+++ b/Terminal.v
@@ -0,0 +1,33 @@
+module Terminal(
+	input clk,
+	
+	input cp_req,
+	input [31:0] cp_insn,
+	output reg cp_ack,
+	output reg cp_busy,
+	input cp_rnw,
+	output reg [31:0] cp_read = 0,
+	input [31:0] cp_write);
+	
+	/* Terminal pretends to be cp5. */
+	reg towrite = 0;
+	reg [7:0] data = 0;
+	
+	always @(*)
+	begin
+		towrite = 0;
+		data = 8'hxx;
+		cp_ack = 0;
+		cp_busy = 0;
+		if (cp_req && (cp_rnw == 0) && (cp_insn[27:24] == 4'b1110) && (cp_insn[19:16] == 4'b0000) && (cp_insn[11:8] == 4'h5))
+		begin
+			towrite = 1;
+			data = cp_write[7:0];
+			cp_ack = 1;
+		end
+	end
+	
+	always @(posedge clk)
+		if (towrite)
+			$c("{extern void term_output(unsigned char d); term_output(",data,");}");
+endmodule
diff --git a/system.v b/system.v
index f8479f4..ddbe0b7 100644
--- a/system.v
+++ b/system.v
@@ -63,12 +63,17 @@ module System(input clk);
 	wire memory_out_write_reg;
 	wire [3:0] memory_out_write_num;
 	wire [31:0] memory_out_write_data;
+
+	wire cp_ack_terminal;
+	wire cp_busy_terminal;
+	wire [31:0] cp_read_terminal;
 	
 	wire cp_req;
-	wire cp_ack = 0;
-	wire cp_busy = 0;
+	wire [31:0] cp_insn;
+	wire cp_ack = cp_ack_terminal;
+	wire cp_busy = cp_busy_terminal;
 	wire cp_rnw;
-	wire [31:0] cp_read = 0;
+	wire [31:0] cp_read = cp_read_terminal;
 	wire [31:0] cp_write;
 	
 	wire stall_cause_issue;
@@ -163,6 +168,7 @@ module System(input clk);
 		.outcpsr(execute_out_cpsr), .outspsr(execute_out_spsr));
 	assign execute_out_backflush = jmp;
 	
+	assign cp_insn = insn_out_execute;
 	Memory memory(
 		.clk(clk), .Nrst(1'b0),
 		/* stall? flush? */
@@ -178,6 +184,11 @@ module System(input clk);
 		.out_write_reg(memory_out_write_reg), .out_write_num(memory_out_write_num), 
 		.out_write_data(memory_out_write_data),
 		.cp_req(cp_req), .cp_ack(cp_ack), .cp_busy(cp_busy), .cp_rnw(cp_rnw), .cp_read(cp_read), .cp_write(cp_write));
+	
+	Terminal terminal(	
+		.clk(clk),
+		.cp_req(cp_req), .cp_insn(cp_insn), .cp_ack(cp_ack_terminal), .cp_busy(cp_busy_terminal), .cp_rnw(cp_rnw),
+		.cp_read(cp_read_terminal), .cp_write(cp_write));
 
 	reg [31:0] clockno = 0;
 	always @(posedge clk)
diff --git a/testbench.cpp b/testbench.cpp
index 4188d71..53be841 100644
--- a/testbench.cpp
+++ b/testbench.cpp
@@ -1,8 +1,30 @@
 #include "Vsystem.h"
 #include <stdio.h>
+#define _XOPEN_SOURCE
+#include <stdlib.h>
+#include <fcntl.h>
 
 Vsystem *top;
 
+void term_output(unsigned char d)
+{
+	int fd = posix_openpt(O_RDWR);
+	static int fd2 = -1;
+	char b[128];
+
+	if (fd2 == -1)
+	{
+		grantpt(fd);  
+		fcntl(fd, F_SETFD, 0);	/* clear close-on-exec */
+		sprintf(b, "rxvt -pty-fd %d -bg black -fg white -title \"Output terminal\" &", fd);
+		system(b);
+		unlockpt(fd);
+		fd2 = open(ptsname(fd), O_RDWR);
+		close(fd);
+	}
+	write(fd2, &d, 1);
+}
+
 unsigned int main_time = 0;
 
 double sc_time_stamp ()
-- 
2.39.2