From ead28dd6fed440ccf4667c459778012bb0d95733 Mon Sep 17 00:00:00 2001
From: "github-classroom[bot]"
 <66690702+github-classroom[bot]@users.noreply.github.com>
Date: Thu, 5 Feb 2026 19:36:36 +0000
Subject: Initial commit

---
 vga-core/vga_address_translator.sv | 39 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 vga-core/vga_address_translator.sv

(limited to 'vga-core/vga_address_translator.sv')

diff --git a/vga-core/vga_address_translator.sv b/vga-core/vga_address_translator.sv
new file mode 100644
index 0000000..cc63fac
--- /dev/null
+++ b/vga-core/vga_address_translator.sv
@@ -0,0 +1,39 @@
+// synopsys translate_off
+`timescale 1 ps / 1 ps
+// synopsys translate_on
+
+/* This module converts a user specified coordinates into a memory address.
+ * The output of the module depends on the resolution set by the user.
+ */
+module vga_address_translator(x, y, mem_address);
+
+	parameter RESOLUTION = "320x240";
+	/* Set this parameter to "160x120" or "320x240". It will cause the VGA adapter to draw each dot on
+	 * the screen by using a block of 4x4 pixels ("160x120" resolution) or 2x2 pixels ("320x240" resolution).
+	 * It effectively reduces the screen resolution to an integer fraction of 640x480. It was necessary
+	 * to reduce the resolution for the Video Memory to fit within the on-chip memory limits.
+	 */
+
+	input [((RESOLUTION == "320x240") ? (8) : (7)):0] x;
+	input [((RESOLUTION == "320x240") ? (7) : (6)):0] y;
+	output reg [((RESOLUTION == "320x240") ? (16) : (14)):0] mem_address;
+
+	/* The basic formula is address = y*WIDTH + x;
+	 * For 320x240 resolution we can write 320 as (256 + 64). Memory address becomes
+	 * (y*256) + (y*64) + x;
+	 * This simplifies multiplication a simple shift and add operation.
+	 * A leading 0 bit is added to each operand to ensure that they are treated as unsigned
+	 * inputs. By default the use a '+' operator will generate a signed adder.
+	 * Similarly, for 160x120 resolution we write 160 as 128+32.
+	 */
+	wire [16:0] res_320x240 = ({1'b0, y, 8'd0} + {1'b0, y, 6'd0} + {1'b0, x});
+	wire [15:0] res_160x120 = ({1'b0, y, 7'd0} + {1'b0, y, 5'd0} + {1'b0, x});
+
+	always @(*)
+	begin
+		if (RESOLUTION == "320x240")
+			mem_address = res_320x240;
+		else
+			mem_address = res_160x120[14:0];
+	end
+endmodule
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