diff --git a/src/devices/system.c b/src/devices/system.c
index 82daa47..543ba24 100644
--- a/src/devices/system.c
+++ b/src/devices/system.c
@@ -116,6 +116,16 @@ system_init(Uxn *u, Uint8 *ram, char *rom)
 
 /* IO */
 
+Uint8
+system_dei(Uxn *u, Uint8 addr)
+{
+	switch(addr) {
+	case 0x4: return u->wst.ptr;
+	case 0x5: return u->rst.ptr;
+	default: return u->dev[addr];
+	}
+}
+
 void
 system_deo(Uxn *u, Uint8 *d, Uint8 port)
 {
@@ -134,6 +144,12 @@ system_deo(Uxn *u, Uint8 *d, Uint8 port)
 				ram[dst + (Uint16)(b_addr + i)] = ram[src + (Uint16)(a_addr + i)];
 		}
 		break;
+	case 0x4:
+		u->wst.ptr = d[4];
+		break;
+	case 0x5:
+		u->rst.ptr = d[5];
+		break;
 	case 0xe:
 		system_inspect(u);
 		break;
diff --git a/src/devices/system.h b/src/devices/system.h
index 1a3cd2a..316dfc1 100644
--- a/src/devices/system.h
+++ b/src/devices/system.h
@@ -9,9 +9,9 @@ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 WITH REGARD TO THIS SOFTWARE.
 */
 
-#define SYSTEM_VERSION 1
-#define SYSTEM_DEIMASK 0x0000
-#define SYSTEM_DEOMASK 0xff08
+#define SYSTEM_VERSION 2
+#define SYSTEM_DEIMASK 0x0030
+#define SYSTEM_DEOMASK 0xff38
 
 #define RAM_PAGES 0x10
 
@@ -24,4 +24,5 @@ int system_version(Uxn *u, char *emulator, char *date);
 int system_error(char *msg, const char *err);
 int system_init(Uxn *u, Uint8 *ram, char *rom);
 
+Uint8 system_dei(Uxn *u, Uint8 addr);
 void system_deo(Uxn *u, Uint8 *d, Uint8 port);
diff --git a/src/uxn11.c b/src/uxn11.c
index e6d98cd..3ab8137 100644
--- a/src/uxn11.c
+++ b/src/uxn11.c
@@ -49,6 +49,7 @@ Uint8
 emu_dei(Uxn *u, Uint8 addr)
 {
 	switch(addr & 0xf0) {
+	case 0x00: return system_dei(u, addr);
 	case 0x20: return screen_dei(u, addr);
 	case 0xc0: return datetime_dei(u, addr);
 	}
diff --git a/src/uxncli.c b/src/uxncli.c
index 001eced..65082ba 100644
--- a/src/uxncli.c
+++ b/src/uxncli.c
@@ -24,6 +24,7 @@ Uint8
 emu_dei(Uxn *u, Uint8 addr)
 {
 	switch(addr & 0xf0) {
+	case 0x00: return system_dei(u, addr);
 	case 0xc0: return datetime_dei(u, addr);
 	}
 	return u->dev[addr];
@@ -73,7 +74,7 @@ main(int argc, char **argv)
 	system_connect(&u, 0xc, DATETIME_VERSION, DATETIME_DEIMASK, DATETIME_DEOMASK);
 	/* Read flags */
 	if(argv[i][0] == '-' && argv[i][1] == 'v')
-		return system_version(&u, "Uxncli - Console Varvara Emulator", "17 Aug 2023");
+		return system_version(&u, "Uxncli - Console Varvara Emulator", "19 Aug 2023");
 	if(!system_init(&u, (Uint8 *)calloc(0x10000 * RAM_PAGES, sizeof(Uint8)), argv[i++]))
 		return system_error("Init", "Failed to initialize uxn.");
 	/* Game Loop */