diff --git a/src/kernal/arnitech/arnitech_net.s b/src/kernal/arnitech/arnitech_net.s
index a4a9c26f..a391b817 100644
--- a/src/kernal/arnitech/arnitech_net.s
+++ b/src/kernal/arnitech/arnitech_net.s
@@ -273,7 +273,12 @@ arnitech_net_copy:
 	tax
 	bvs @2
 	lda (SAL), y
-	sta RRNET_RX_TX_DATA, x
+	cpx #$01                           ; plain stores: an indexed one reads the port
+	beq @7                             ; first, which takes a byte of a received frame
+	sta RRNET_RX_TX_DATA+0
+	bvc @3                             ; branch always
+@7:
+	sta RRNET_RX_TX_DATA+1
 	bvc @3                             ; branch always
 @2:
 	lda RRNET_RX_TX_DATA, x