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CPM OPERATING SYSTEMS/CPM 68K/1.0X SOURCES/v101/ddt/examine.c

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+/****************************************************************/
+/*                                                              */
+/*      Examine/Alter CPU Registers                             */
+/*                                                              */
+/****************************************************************/
+ 
+#include "ddtinc.h"
+ 
+examine(cx, statep)
+char *cx;
+struct cpustate *statep;
+{
+        if        (nomore(cx))    showstate(statep);
+        else if (*++cx == 'D')    pdareg('D', cx, statep->dreg);
+        else if   (*cx == 'A')    pdareg('A', cx, statep->areg);
+        else if (cmp("PC",--cx))  preg("PC", &(statep->pc));
+        else if (cmp("USP",cx))   { if (preg("USP",&(statep->usp)) &&
+                                        ((statep->status & SUPER) == 0 ))
+                                        statep->areg[7] = statep->usp;
+             }
+        else if (cmp("SSP",cx))   { if (preg("SSP",&(statep->ssp)) &&
+                                        (statep->status & SUPER)  )
+                                        statep->areg[7] = statep->ssp;
+             }
+        else                      tryflags(cx, statep); 
+}
+ 
+ 
+ 
+showstate(statep)
+register struct cpustate *statep;
+{
+        register short int status;
+ 
+        stout("PC=");  puthexl(statep->pc);  putchar(' ');
+        stout("USP="); puthexl(statep->usp); putchar(' ');
+        stout("SSP="); puthexl(statep->ssp); putchar(' ');
+        stout("ST=");  puthexw(status = statep->status);
+        stout("=>");
+        if (status & TRACE)  stout("TR ");
+        if (status & SUPER)  stout("SUP ");
+        stout("IM=");  putchar(((status & INTMSK)>>8)+'0');
+        if (status & EXTEND) stout(" EXT");
+        if (status & NEG)    stout(" NEG");
+        if (status & ZERO)   stout(" ZER");
+        if (status & OFLOW)  stout(" OFL");
+        if (status & CARRY)  stout(" CRY");
+        putchar('\n');
+        pregrow('D', statep->dreg);     /* D registers */
+        pregrow('A', statep->areg);     /* A registers */
+        dot = statep -> pc;
+        pinstr();                       /* disassembled instruction */
+        putchar('\n');
+}
+ 
+ 
+ 
+pdareg(da, cx, rp)      /* print data or address register contents */
+char  da;
+register char *cx;
+long *rp;
+{
+ 
+        char str[3];
+ 
+        if ( ('0' <= *++cx) && (*cx <= '7') && nomore(cx) ) {
+                str[0] = da;
+                str[1] = *cx;
+                str[2] = 0;
+                preg(str, rp + *cx - '0');
+        }
+}
+ 
+ 
+preg(rname, regp)       /* print register contents */
+register char *rname;
+register long *regp;
+{
+        char buf[BUFLEN];
+        register short int nc;
+        long int newval;
+        char *bp;
+        register int modify; 
+ 
+        modify = 0;
+        stout(rname);
+        putchar('=');
+        puthexl(*regp);
+        putchar(' ');
+        *buf = BUFLEN-2;
+        BDOS(READBUF, buf);
+	putchar('\n');
+        if ((nc=buf[1])>0) {
+                buf[nc+2]=0;
+                bp = buf + 1;
+                while (*++bp) *bp = toupper(*bp);
+                bp = buf + 1;
+                if (gethex(&bp, &newval) && nomore(bp)) {
+                   *regp = newval;
+                   modify = 1;
+                }
+                else if ( ! nomore(buf+1) ) bad();
+        }
+        return(modify);
+}
+ 
+ 
+ 
+pregrow(ch, rowp)
+char ch;
+long *rowp;
+{
+        register int n;
+        
+        putchar(ch);
+        putchar(' ');
+        for (n=0; n<8; n++) {
+                putchar(' ');
+                puthexl(*rowp++);
+                if (n==3) putchar(' ');
+        }
+        putchar('\n');
+}
+ 
+ 
+tryflags(cx, statep)
+register char *cx;
+register struct cpustate *statep;
+{
+        stout("Error or unimplemented function.");
+}
+ 
+ 
+cmp(str, ctl)
+register char *str;
+register char *ctl;
+{
+        while (*str && (*str++ == *++ctl)) ;
+        if ( ( ! *str) && nomore(ctl) ) return(1);
+        else return(0);
+}