-/*
- * _6526.h
- *
- * Ullrich von Bassewitz, 22.09.1998
- *
- * Internal include file, do not use directly.
- *
- */
+/*****************************************************************************/
+/* */
+/* _6526.h */
+/* */
+/* Internal include file, do not use directly */
+/* */
+/* */
+/* */
+/* (C) 1998-2000 Ullrich von Bassewitz */
+/* Wacholderweg 14 */
+/* D-70597 Stuttgart */
+/* EMail: uz@musoftware.de */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
-/* 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 */
};
projects / cc65 / blobdiff