From 072b0266af70ce51eacad08831950e5ebcb2ea8a Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 9 Nov 2019 20:12:09 -0500
Subject: [PATCH] It seems status reads are not  required to clear the
 interrupt line.

---
 Components/6850/6850.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Components/6850/6850.cpp b/Components/6850/6850.cpp
index c61c4bb4d..9b08ca8eb 100644
--- a/Components/6850/6850.cpp
+++ b/Components/6850/6850.cpp
@@ -25,7 +25,6 @@ uint8_t ACIA::read(int address) {
 		received_data_ |= NoValueMask;
 		return uint8_t(received_data_);
 	} else {
-		clear_interrupt_cause(StatusNeedsRead);
 		return
 			((received_data_ & NoValueMask) ? 0x00 : 0x01) |
 			((next_transmission_ == NoValueMask) ? 0x02 : 0x00) |
@@ -176,7 +175,7 @@ void ACIA::set_interrupt_delegate(InterruptDelegate *delegate) {
 
 void ACIA::add_interrupt_cause(int cause) {
 	const bool is_changing_state = !interrupt_causes_;
-	interrupt_causes_ |= cause | StatusNeedsRead;
+	interrupt_causes_ |= cause;
 	if(interrupt_delegate_ && is_changing_state)
 		interrupt_delegate_->acia6850_did_change_interrupt_status(this);
 }