From 38531bc9831bbf3300bcfb134d164cfa7461d239 Mon Sep 17 00:00:00 2001
From: Phillip Stevens <phillip.stevens@gmail.com>
Date: Tue, 9 Feb 2021 18:11:40 +1100
Subject: [PATCH] acia - receive test optimisation

---
 Source/HBIOS/acia.asm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Source/HBIOS/acia.asm b/Source/HBIOS/acia.asm
index 2c440023..1dc69bdd 100644
--- a/Source/HBIOS/acia.asm
+++ b/Source/HBIOS/acia.asm
@@ -180,8 +180,8 @@ ACIA_INTRCV:
         ; CHECK TO SEE IF SOMETHING IS ACTUALLY THERE
         LD      C,(IY+3)                ; CMD/STAT PORT TO C
         IN      A,(C)                   ; GET STATUS
-        AND     $01                     ; ISOLATE RECEIVE READY BIT
-        RET     Z                       ; NOTHING AVAILABLE ON CURRENT CHANNEL
+        RRA                             ; READY BIT TO CF
+        RET     NC                      ; NOTHING AVAILABLE ON CURRENT CHANNEL
 ;
 ACIA_INTRCV1:
         ; RECEIVE CHARACTER INTO BUFFER