X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=include%2F_6526.h;h=aa3158dc8c3d69e53801f171ac08912f4ec36cde;hb=2cd4b5109a59c3743b38369359c389cc1b9edab4;hp=2e72aec48ed38523af42d1d04ca6a5a4cdced7fe;hpb=a17dee1a1c8b135377d40b2ca4dc56fb16fd4446;p=cc65

diff --git a/include/_6526.h b/include/_6526.h
index 2e72aec48..aa3158dc8 100644
--- a/include/_6526.h
+++ b/include/_6526.h
@@ -1,8 +1,8 @@
 /*****************************************************************************/
 /*                                                                           */
-/*				    _6526.h				     */
+/*                                  _6526.h                                  */
 /*                                                                           */
-/*		  Internal include file, do not use directly		     */
+/*                Internal include file, do not use directly                 */
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
@@ -38,24 +38,28 @@
 
 
 
-/* Define a structure with the 6526 register offsets */
+/* Define a structure with the 6526 register offsets.
+** NOTE: The timer registers are not declared as 16 bit registers, because
+** the order in which the two 8 bit halves are written is important, and
+** the compiler doesn't guarantee any order when writing 16 bit values.
+*/
 struct __6526 {
-    unsigned char	pra;		/* Port register A */
-    unsigned char	prb;		/* Port register B */
-    unsigned char	ddra;		/* Data direction register A */
-    unsigned char	ddrb;		/* Data direction register B */
-    unsigned char	ta_lo;		/* Timer A, low byte */
-    unsigned char	ta_hi;		/* Timer A, high byte */
-    unsigned char      	tb_lo; 	       	/* Timer B, low byte */
-    unsigned char	tb_hi;		/* Timer B, high byte */
-    unsigned char      	tod_10;		/* TOD, 1/10 sec. */
-    unsigned char	tod_sec;	/* TOD, seconds */
-    unsigned char	tod_min;	/* TOD, minutes */
-    unsigned char	tod_hour;	/* TOD, hours */
-    unsigned char	sdr;		/* Serial data register */
-    unsigned char	icr;		/* Interrupt control register */
-    unsigned char	cra;		/* Control register A */
-    unsigned char	crb;		/* Control register B */
+    unsigned char       pra;            /* Port register A */
+    unsigned char       prb;            /* Port register B */
+    unsigned char       ddra;           /* Data direction register A */
+    unsigned char       ddrb;           /* Data direction register B */
+    unsigned char       ta_lo;          /* Timer A, low byte */
+    unsigned char       ta_hi;          /* Timer A, high byte */
+    unsigned char       tb_lo;          /* Timer B, low byte */
+    unsigned char       tb_hi;          /* Timer B, high byte */
+    unsigned char       tod_10;         /* TOD, 1/10 sec. */
+    unsigned char       tod_sec;        /* TOD, seconds */
+    unsigned char       tod_min;        /* TOD, minutes */
+    unsigned char       tod_hour;       /* TOD, hours */
+    unsigned char       sdr;            /* Serial data register */
+    unsigned char       icr;            /* Interrupt control register */
+    unsigned char       cra;            /* Control register A */
+    unsigned char       crb;            /* Control register B */
 };