Merge pull request #5 from Ripjetski6502/IsSD

v1.47

README.md

@@ -31,6 +31,8 @@ Version 1.45 brings GStat() function to display simple non-interactive status wi
 
 Version 1.46 brings A8LibDOS, which includes the function SDGDate().  SDGDate() retrieves the date and time from the SpartaDOS COMTAB table, which is independent of the actual real time clock being used.
 
+Version 1.47 brings IsSD() to A8LibDOS, which detects and returns if SpartaDOS is present or not.
+
 License: GNU General Public License v3.0
 
 See the LICENSE file for full license information.

src/a8defdos.h

@@ -15,6 +15,9 @@
 // Definitions
 // --------------------------------------------------
 
+// Locations
+#define DOSID *((word *) 0x0F31)
+
 // Date/Time function buffer elements
 #define ASD_DT_DY  0
 #define ASD_DT_MO  1
@@ -27,6 +30,7 @@
 // --------------------------------------------------
 // Function Prototypes
 // --------------------------------------------------
+unsigned char IsSD(void);
 void SDGDate(unsigned char *bD);
 
 #endif

src/a8libdos.c

@@ -16,6 +16,25 @@
 #include "a8defdos.h"
 
 
+// ------------------------------------------------------------
+// Func...: byte IsSD(void)
+// Desc...: Determines if SpartaDOS is present
+// Returns: TRUE or FALSE
+// ------------------------------------------------------------
+byte IsSD(void)
+{
+    byte bR = FALSE;
+    byte bP = DOSID;
+
+    // Check DOSID for one of 4 bytes indicating SpartaDOS
+    if ((bP == 0) || (bP == 15) || (bP == 68) || (bP ==89)) {
+        bR = TRUE;
+    }
+
+    return (bR);
+}
+
+
 // ------------------------------------------------------------
 // Func...: void SDGDate(unsigned char *bD)
 // Desc...: Gets date and time from SpartaDOS