Merge branch 'board-io' into 'master'

Add board-io, replace sevenseg in sw

See merge request bslathi19/super6502!8

hw/fpga/addr_decode.sv

@@ -5,7 +5,8 @@ module addr_decode(
     output logic rom_cs,
     output logic hex_cs,
     output logic uart_cs,
-    output logic irq_cs
+    output logic irq_cs,
+    output logic board_io_cs
 );
 
 assign rom_cs = addr >= 16'h8000;
@@ -13,6 +14,7 @@ assign ram_cs = addr < 16'h4000;
 assign sdram_cs = addr >= 16'h4000 && addr < 16'h7ff0;
 assign hex_cs = addr >= 16'h7ff0 && addr < 16'h7ff4;
 assign uart_cs = addr >= 16'h7ff4 && addr < 16'h7ff6;
+assign board_io_cs = addr == 16'h7ff6;
 assign irq_cs  = addr == 16'h7fff;
 
 endmodule

hw/fpga/board_io.sv

@@ -0,0 +1,27 @@
+module board_io(
+    input clk,
+    input rst,
+    
+    input rw,
+
+    input [7:0] data_in,
+    input cs,
+    input [1:0] addr,
+    
+    output logic [7:0] data_out,
+
+    output logic [7:0] led,
+    input [7:0] sw
+);
+
+assign data_out = sw;
+
+
+always_ff @(posedge clk) begin
+    if (rst)
+        led = '0;
+    if (~rw & cs)
+        led <= data_in;
+end
+
+endmodule

hw/fpga/hvl/cs_testbench.sv

@@ -9,10 +9,11 @@ logic ram_cs;
 logic sdram_cs;
 logic rom_cs;
 logic hex_cs;
+logic board_io_cs;
 logic uart_cs;
 logic irq_cs;
 
-int cs_count = ram_cs + sdram_cs + rom_cs + hex_cs + uart_cs;
+int cs_count = ram_cs + sdram_cs + rom_cs + hex_cs + uart_cs + board_io_cs;
 
 addr_decode dut(.*);
 
@@ -44,6 +45,11 @@ initial begin : TEST_VECTORS
             else
                 $error("Bad CS! addr=%4x should have uart_cs!", addr);
         end
+        if (i == 16'h7ff6) begin
+            assert(board_io_cs == '1)
+            else
+                $error("Bad CS! addr=%4x should have board_io_cs!", addr);
+        end
         if (i == 16'h7fff) begin
             assert(irq_cs == '1)
             else

hw/fpga/super6502.sv

@@ -26,6 +26,9 @@ module super6502(
     input   logic           UART_RXD,
     output  logic           UART_TXD,
 
+    input [7:0] SW,
+    output [7:0] LED,
+
     ///////// SDRAM /////////
     output             DRAM_CLK,
     output             DRAM_CKE,
@@ -57,6 +60,7 @@ logic [7:0] ram_data_out;
 logic [7:0] sdram_data_out;
 logic [7:0] uart_data_out;
 logic [7:0] irq_data_out;
+logic [7:0] board_io_data_out;
 
 logic ram_cs;
 logic sdram_cs;
@@ -64,6 +68,7 @@ logic rom_cs;
 logic hex_cs;
 logic uart_cs;
 logic irq_cs;
+logic board_io_cs;
 
 cpu_clk cpu_clk(
 	.inclk0(clk_50),
@@ -88,7 +93,8 @@ addr_decode decode(
     .rom_cs(rom_cs),
     .hex_cs(hex_cs),
     .uart_cs(uart_cs),
-    .irq_cs(irq_cs)
+    .irq_cs(irq_cs),
+    .board_io_cs(board_io_cs)
 );
 
 
@@ -103,6 +109,8 @@ always_comb begin
         cpu_data_out = uart_data_out;
     else if (irq_cs)
         cpu_data_out = irq_data_out;
+    else if (board_io_cs)
+        cpu_data_out = board_io_data_out;
     else
         cpu_data_out = 'x;
 end
@@ -157,6 +165,17 @@ SevenSeg segs(
     .HEX0(HEX0), .HEX1(HEX1), .HEX2(HEX2), .HEX3(HEX3), .HEX4(HEX4), .HEX5(HEX5)
 );
 
+board_io board_io(
+    .clk(clk),
+    .rst(rst),
+    .rw(cpu_rwb),
+    .data_in(cpu_data_in),
+    .data_out(board_io_data_out),
+    .cs(board_io_cs),
+    .led(LED),
+    .sw(SW)
+);
+
 logic uart_irq;
 
 uart uart(

sw/board_io.h

@@ -1,5 +1,5 @@
-#ifndef _SEVEN_SEG
+#ifndef _BOARD_IO_H
-#define _SEVEN_SEG
+#define _BOARD_IO_H
 
 #include <stdint.h>
 
@@ -9,4 +9,8 @@ uint8_t hex_set_24(uint32_t val);
 
 void hex_enable(uint8_t mask);
 
+uint8_t sw_read();
+
+void led_set(uint8_t val);
+
 #endif

sw/board_io.s

@@ -6,6 +6,8 @@
 .export _hex_set_16
 .export _hex_set_24
 .export _hex_enable
+.export _sw_read
+.export _led_set
 
 .autoimport	on
 
@@ -52,4 +54,18 @@ _hex_set_24:
 ; Set the mask for seven seg enables
 _hex_enable:
         sta SEVEN_SEG+3
+        rts
+
+; @out A: The Value of the switches
+; Reads the current values of the switches.
+_sw_read:
+        lda SW
+        ldx #$0
+        rts
+
+; @in A: val
+; @out A: 0 for success, 1 for failure
+; Sets the LEDs
+_led_set:
+        sta LED
         rts

sw/io.inc65

@@ -5,4 +5,7 @@ UART_TXB    = UART
 UART_RXB    = UART
 UART_STATUS = UART + 1
 
+LED         = $7ff6
+SW          = LED
+
 IRQ_STATUS  = $7fff

sw/irq.c

@@ -4,7 +4,6 @@
 
 #include "interrupt.h"
 #include "uart.h"
-#include "sevenseg.h"
 
 char lastchar;
 

sw/main.c

@@ -1,11 +1,12 @@
 #include <stdint.h>
 #include <conio.h>
 
-#include "sevenseg.h"
+#include "board_io.h"
 #include "uart.h"
 
 int main() {
     int i;
+    uint8_t sw;
     char s[16];
     s[15] = 0;
 
@@ -13,6 +14,10 @@ int main() {
     cprintf("Hello, world!\n");
 
     while (1) {
+
+        sw = sw_read();
+        led_set(sw);
+
         cscanf("%15s", s);
         cprintf("\n");
         for (i = 0; i < 16; i++)

sw/tests/test_main.c

@@ -1,6 +1,6 @@
 #include <stdio.h>
 
-#include "sevenseg.h"
+#include "board_io.h"
 #include "uart.h"
 #include "interrupt.h"