diff --git a/src/kernal/iec/iec_tx_byte.s b/src/kernal/iec/iec_tx_byte.s
index 93c42625..014dca9e 100644
--- a/src/kernal/iec/iec_tx_byte.s
+++ b/src/kernal/iec/iec_tx_byte.s
@@ -51,6 +51,17 @@ iec_tx_byte:
 	+phx_trash_a
 	+phy_trash_a
 
+	; A listener holds DATA until we release CLK; if nobody pulls it
+	; within 256us, no device is present - see https://www.pagetable.com/?p=1135
+	ldx #$18
+@0:
+	lda CIA2_PRA
+	bpl @1                             ; branch if DATA is pulled
+	dex
+	bne @0
+	jsr kernalstatus_DEVICE_NOT_FOUND
+	jmp iec_return_DEVICE_NOT_FOUND
+@1:
 	; Notify all devices that we are going to send a byte
 	; and it is going to be a data byte (released ATN)
 	jsr iec_release_atn_clk_data