From b01de82fd1ffcb7b76e3baa86af21c627588307e Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Thu, 16 Apr 2020 08:18:55 -0400
Subject: [PATCH] drv/acia: latest bells and whistles

---
 drv/acia.fs  |  4 ++--
 drv/acia.z80 | 61 ++++++++++++++++++++++++++--------------------------
 2 files changed, 33 insertions(+), 32 deletions(-)

diff --git a/drv/acia.fs b/drv/acia.fs
index 2de4836..7670d45 100644
--- a/drv/acia.fs
+++ b/drv/acia.fs
@@ -29,7 +29,7 @@ ACIA_MEM: Address in memory that can be used variables shared
 
 : ACIA$
     H@ DUP DUP ACIA( ! ACIAR> !
-    1 + ACIAW> ! ( write index starts one position later )
+    1+ ACIAW> ! ( write index starts one position later )
     ACIABUFSZ ALLOT
     H@ ACIA) !
 ( setup ACIA
@@ -49,7 +49,7 @@ ACIA_MEM: Address in memory that can be used variables shared
 
 : KEY
     ( inc then fetch )
-    ACIAR> @ 1 + DUP ACIA) @ = IF
+    ACIAR> @ 1+ DUP ACIA) @ = IF
         DROP ACIA( @
     THEN
 
diff --git a/drv/acia.z80 b/drv/acia.z80
index 2903ec5..0eb2434 100644
--- a/drv/acia.z80
+++ b/drv/acia.z80
@@ -20,37 +20,38 @@ ACIA_MEM
 	( Read our character from ACIA into our BUFIDX )
     ACIA_CTL INAn,
     0x01 ANDn,   ( is ACIA rcv buf full? )
-    JRZ, L2 FWR ( end, no, wrong interrupt cause. )
+    IFNZ,
+        ( correct interrupt cause )
+        ( +2 == ACIAW> )
+        ACIA_MEM 2+ LDHL(nn),
+        ( is it == to ACIAR>? )
+        ( +0 == ACIAR> )
+        DE ACIA_MEM LDdd(nn),
+        ( carry cleared from ANDn above )
+        DE SBCHLss,
+        IFNZ, ( buffer full? )
+            ( no, continue )
+            DE ADDHLss, ( restore ACIAW> )
+            ( buffer not full, let's write )
+            ACIA_IO INAn,
+            (HL) A LDrr,
 
-    ( +2 == ACIAW> )
-    ACIA_MEM 2 + LDHL(nn),
-    ( is it == to ACIAR>? )
-    ( +0 == ACIAR> )
-    DE ACIA_MEM LDdd(nn),
-    ( carry cleared from ANDn above )
-    DE SBCHLss,
-    JRZ, L3 FWR ( end, buffer full )
-
-    DE ADDHLss, ( restore ACIAW> )
-    ( buffer not full, let's write )
-    ACIA_IO INAn,
-    (HL) A LDrr,
-
-    ( advance W> )
-    HL INCss,
-    ( +2 == ACIAW> )
-    ACIA_MEM 2 + LD(nn)HL,
-    ( +6 == ACIA) )
-    DE ACIA_MEM 6 + LDdd(nn),
-    DE SUBHLss,
-    JRNZ, L4 FWR ( skip )
-    ( end of buffer reached )
-    ( +4 == ACIA( )
-    ACIA_MEM 4 + LDHL(nn),
-    ( +2 == ACIAW> )
-    ACIA_MEM 2 + LD(nn)HL,
-L4 FSET ( skip )
-L3 FSET L2 FSET ( end )
+            ( advance W> )
+            HL INCss,
+            ( +2 == ACIAW> )
+            ACIA_MEM 2+ LD(nn)HL,
+            ( +6 == ACIA) )
+            DE ACIA_MEM 6 + LDdd(nn),
+            DE SUBHLss,
+            IFZ, ( end of buffer reached? )
+                ( yes )
+                ( +4 == ACIA( )
+                ACIA_MEM 4 + LDHL(nn),
+                ( +2 == ACIAW> )
+                ACIA_MEM 2+ LD(nn)HL,
+            THEN,
+        THEN,
+    THEN,
 
     DE POPqq,
     HL POPqq,