16_ca needs huge amounts of work and I should remember what needs to be done soon...

[16.git] / 16 / modex16 / dos_kb.c

diff --git a/16/modex16/dos_kb.c b/16/modex16/dos_kb.c
new file mode 100755 (executable)
index 0000000..dd92418
--- /dev/null
+++ b/16/modex16/dos_kb.c
@@ -0,0 +1,142 @@
+/* Thanks to Alex Russell for example code */
+/* Thanks to Gary Neal for example code */
+#include "dos_kb.h"
+
+// keyboard buffer
+static byte key[NUM_SCANCODES]; // pressed
+static byte kea[NUM_SCANCODES]; // released
+
+#ifdef __cplusplus             /* Function must be declared C style */
+extern "C" {
+#endif
+static void interrupt (far *oldkb)(void) = NULL; /* BIOS keyboard handler */
+#ifdef __cplusplus
+}
+#endif
+
+/*
+ * Comment out the following #define if you don't want the testing main()
+ * to be included.
+ */
+//#define TESTING
+#define TESTING2
+
+/*****************NEW KEYBOARD 09h ISR***********************/
+void interrupt newkb(void){
+       byte kee;
+       register char qx;
+
+       kee = inp(0x60);        /* Read the keyboard scan code */
+
+       /* Clear keyboard controller on XT machines */
+       qx = inp(0x61);    /* Get keyboard control register */
+       qx |= 0x82;
+       outp(0x61, qx);    /* Toggle acknowledge bit high */
+       qx &= 0x7F;
+       outp(0x61, qx);    /* Toggle acknowledge bit low */
+
+       /* Interpret the scan code and set our flags */
+       #ifdef TESTING2
+       //printf("%d[%d]\n",kee,key[kee]);
+       printf("\0"); // bug
+       #endif
+       if(kee & 0x80)
+               key[kee & 0x7F] = 0; // a key is released
+       else
+               key[kee] = kea[kee] = 1; // a key is pressed
+
+       /* Acknowledge the interrupt to the programmable interrupt controller */
+       outp(0x20, 0x20);      /* Signal non specific end of interrupt */
+}
+
+/* ---------------------- init_keyboard() ---------------- April 17,1993 */
+/* restore the bios keyboard handler */
+/* ---------------------- deinit_keyboard() -------------- April 17,1993 */
+void setkb(int vq){
+       int i;  /* Index variable */
+       if(!vq){ // deinitiation
+               /* Abort if our function pointer has no valid address */
+               if(oldkb == NULL) return;
+               /* Set address in our function pointer in interrupt vector table */
+               _dos_setvect(9, oldkb);
+               /* Reset our function pointer to contain no valid address */
+               oldkb = NULL;
+               #ifdef TESTING
+               /* Print the key heap */
+               printf("\n");
+               for(i=0; i<NUM_SCANCODES; i++){
+                       if(i==NUM_SCANCODES/2) printf("================================\n");
+                       printf("%03d[%d][%d]",i+1,key[i],kea[i]);
+                       if(key[i]==1)printf("====");
+                       printf(",\n");
+               }
+               #endif
+       }else if(vq == 1){ // initiation
+               byte far *lock_key;
+
+               /* Abort if our function pointer has a valid address. */
+               if(oldkb != NULL) return;
+
+               /* Clear the keyboard buttons state arrays */
+               for(i = 0; i < NUM_SCANCODES; i++)
+                       key[i] = kea[i] = 0;
+
+               /* save old BIOS key board handler */
+               oldkb = _dos_getvect(9);
+
+               // turn off num-lock via BIOS
+               lock_key = MK_FP(0x040, 0x017); // Pointing to the address of the bios shift state keys
+               *lock_key&=(~(16 | 32 | 64)); // toggle off the locks by changing the values of the 4th, 5th, and 6th bits of the address byte of 0040:0017
+               oldkb();        // call BIOS keyhandler to change keyboard lights
+
+               /* setup our own handler */
+               _dos_setvect(9, newkb);
+       }
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
+ * keyp                                                              *
+ *                                                                      *
+ * Returns the status of the key requested.                            *
+ * The status is 1 if the key is pressed or has been pressed since the     *
+ * last call to this function for that particular key.              *
+\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+int keyp(byte c){
+       register char retVal;
+
+       /* Key value in range of keyboard keys available */
+       c &= 0x7F;
+
+       /* Get the status of the key requested */
+       retVal = key[c] | kea[c];
+
+       /* Reset the was pressed status for the requested key */
+       kea[c] = 0;
+
+       /* Return the requested key's state */
+       return retVal;
+}
+
+
+/*
+ * The library testing routines follows below.
+ */
+
+#ifdef TESTING
+
+/*
+ * Library test (program) entry point.
+ */
+
+void main(void)
+{
+       byte q;
+       setkb(1);
+       while(!keyp(1))
+       {
+               keyp(q);
+       }
+       setkb(0);
+}
+
+#endif