feat: impelement a barebones SRAM

src/bus/Sram.zig

@@ -0,0 +1,31 @@
+const std = @import("std");
+
+const Allocator = std.mem.Allocator;
+const log = std.log.scoped(.SRAM);
+const Self = @This();
+
+buf: []u8,
+alloc: Allocator,
+
+pub fn init(alloc: Allocator) !Self {
+    // FIXME: SRAM is more than just a 64KB block of memory
+    const buf = try alloc.alloc(u8, 0x10000);
+    std.mem.set(u8, buf, 0);
+
+    return Self{
+        .buf = buf,
+        .alloc = alloc,
+    };
+}
+
+pub fn deinit(self: Self) void {
+    self.alloc.free(self.buf);
+}
+
+pub fn get8(self: *const Self, idx: usize) u8 {
+    return self.buf[idx];
+}
+
+pub fn set8(self: *Self, idx: usize, byte: u8) void {
+    self.buf[idx] = byte;
+}