diff --git a/rtl837x_common.h b/rtl837x_common.h
index ef8d4d6..57c0e6a 100644
--- a/rtl837x_common.h
+++ b/rtl837x_common.h
@@ -36,8 +36,21 @@
 // the RTL_FRAME_TAG_ID is used as part of an 8-byte tag. When VLAN is activated,
 // the VLAN tag is inserted after the RTL tag
 // See here for the RTL tag: https://github.com/torvalds/linux/commit/1521d5adfc2b557e15f97283c8b7ad688c3ebc40
-#define RTL_TAG_SIZE		8
-#define VLAN_TAG_SIZE		4
+struct rtl_tag {
+	uint16_t tag;		// This is 0x8899 for the RTL837X
+	uint8_t version;	// Version is 4
+	uint8_t reason;
+	uint16_t flags;
+	uint16_t pmask;		// A bit mask for a TX pkt, 4-bit port-number for RX
+};
+
+struct vlan_tag {
+	uint16_t svlan;		// Service VLAN
+	uint16_t vlan;
+};
+
+#define RTL_TAG_SIZE		(sizeof (struct rtl_tag))
+#define VLAN_TAG_SIZE		(sizeof (struct vlan_tag))
 #define RTL_FRAME_TAG_ID	0x8899
 
 // For RX and TX, an 8 byte header describing the frame to be moved to the Asic
@@ -70,15 +83,6 @@ struct flash_region_t {
 
 extern __xdata uint8_t uip_buf[UIP_CONF_BUFFER_SIZE+2];
 
-// 8899 04 0000 20 0004
-struct rtl_tag {
-	uint16_t tag;
-	uint8_t version;
-	uint8_t reason;
-	uint16_t flags;
-	uint16_t pmask;  // A bit mask for a TX pkt, 4-bit port-number for RX
-};
-
 // Headers for calls in the common code area (HOME/BANK0)
 void print_string(__code char *p);
 void print_long(__xdata uint32_t a);
diff --git a/rtl837x_regs.h b/rtl837x_regs.h
index 402b5c0..2610d95 100644
--- a/rtl837x_regs.h
+++ b/rtl837x_regs.h
@@ -93,11 +93,14 @@
  */
 #define RTL837X_REG_NIC_BUFFSIZE_TX	0x7844
 #define RTL837X_REG_NIC_RXBUFF_RX	0x7848
+#define RTL837X_REG_NIC_RXCMD		0x784c
+#define RTL837X_REG_NIC_TXCMD		0x7850
 #define RTL837X_REG_RX_CTRL		0x785c
 #define RTL837X_REG_TX_CTRL		0x7860
-#define RTL837X_REG_RX_AVAIL		0x7874
-#define RTL837X_REG_RX_RINGPTR		0x787c
-#define RTL837X_REG_RX_DONE		0x784c
+#define RTL837X_REG_NIC_RX_BUFF_DATA	0x7874
+#define RTL837X_REG_CPU_RX_CURR_PKT	0x787c
+#define RTL837X_REG_NIC_TX_CURR_PKT	0x7884
+#define RTL837X_REG_CPU_TX_CURR_PKT	0x7890
 #define RTL837X_REG_CPU_TAG		0x6720
 #define RTL837X_REG_CPU_TAG_AWARE_PMASK	0x603C
 #define RTL837X_REG_MAC_FORCE_MODE	0x6344
diff --git a/rtlplayground.c b/rtlplayground.c
index c8ad2c9..5257448 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -819,7 +819,7 @@ void tcpip_output(void)
 	uip_buf[VLAN_TAG_SIZE + 2] = uip_buf[VLAN_TAG_SIZE + 3] = 0;
 	uip_buf[VLAN_TAG_SIZE + 6] = uip_buf[VLAN_TAG_SIZE + 7] = 0;
 
-	reg_read_m(0x7890);
+	reg_read_m(RTL837X_REG_CPU_TX_CURR_PKT);
 	uint16_t ring_ptr = ((uint16_t)sfr_data[2]) << 8;
 	ring_ptr |= sfr_data[3];
 
@@ -835,20 +835,20 @@ void tcpip_output(void)
 	// Move data over from xmem buffer to ASIC side using DMA
 	nic_tx_packet(ring_ptr);
 
-	reg_read_m(0x7884);  // actual bytes sent, for now we assume everything worked
+	// New position of the ring-pointer on the NIC-side indicates number of bytes transmitted
+	reg_read_m(RTL837X_REG_NIC_TX_CURR_PKT);
 
 	// Do actual TX of data on ASIC side
-	sfr_data[0] = sfr_data[1] = sfr_data[2] = 0;
-	sfr_data[3] = 0x1;
-	reg_write_m(0x7850);
+	REG_SET(RTL837X_REG_NIC_TXCMD, 1);
 }
 
 
 void handle_rx(void)
 {
-	reg_read_m(RTL837X_REG_RX_AVAIL);
+	// Check the amount of data available on the NIC/ASIC side
+	reg_read_m(RTL837X_REG_NIC_RX_BUFF_DATA);
 	if (sfr_data[2] != 0 || sfr_data[3] != 0) {
-		reg_read_m(RTL837X_REG_RX_RINGPTR);
+		reg_read_m(RTL837X_REG_CPU_RX_CURR_PKT);
 		uint16_t ring_ptr = ((uint16_t)sfr_data[2]) << 8;
 		ring_ptr |= sfr_data[3];
 		ring_ptr <<= 3;
@@ -872,16 +872,13 @@ void handle_rx(void)
 			write_char(' ');
 		}
 #endif
-		sfr_data[0] = sfr_data[1] = sfr_data[2] = 0;
-		sfr_data[3] = 0x1;
-		reg_write_m(RTL837X_REG_RX_DONE);
+		REG_SET(RTL837X_REG_NIC_RXCMD, 1);
 		uip_len = (((uint16_t)rx_headers[5]) << 8) | rx_headers[4];
-//		write_char('>'); print_byte(uip_buf[ETHERTYPE_OFFSET]); write_char('<');
-//		write_char('>'); print_byte(uip_buf[ETHERTYPE_OFFSET + 1]); write_char('<');
-		// Check for ARP packet
-		rx_packet_vlan = uip_buf[12 + RTL_TAG_SIZE + 2] & 0xf;
+
+		// Retrieve VLAN from VLAN-tag
+		rx_packet_vlan = uip_buf[2 * sizeof (struct uip_eth_addr) + RTL_TAG_SIZE + 2] & 0xf;
 		rx_packet_vlan <<= 8;
-		rx_packet_vlan |= uip_buf[12 + RTL_TAG_SIZE + 3];
+		rx_packet_vlan |= uip_buf[2 * sizeof (struct uip_eth_addr) + RTL_TAG_SIZE + 3];
 #ifdef RXTXDBG
 		print_string(" RX-VLAN: "); print_short(rx_packet_vlan); write_char('\n');
 		print_string(" RX dst: "); print_byte(uip_buf[0]); print_byte(uip_buf[1]); print_byte(uip_buf[2]);