open-simh · bscottm · Jun 16, 2025 · Jun 16, 2025 · Jun 16, 2025 · Jun 16, 2025
diff --git a/3B2/3b2_mau.h b/3B2/3b2_mau.h
@@ -186,15 +186,15 @@
 #define MAU_RC_RZ         3            /* Round toward Zero        */
 #endif
 
-#define SFP_SIGN(V)  (((V) >> 31) & 1)
+#define SFP_SIGN(V)  ((((V) >> 31) & 1) != 0)
 #define SFP_EXP(V)   (((V) >> 23) & 0xff)
 #define SFP_FRAC(V)  ((V) & 0x7fffff)
 
-#define DFP_SIGN(V)  (((V) >> 63) & 1)
+#define DFP_SIGN(V)  ((((V) >> 63) & 1) != 0)
 #define DFP_EXP(V)   (((V) >> 52) & 0x7ff)
 #define DFP_FRAC(V)  ((V) & 0xfffffffffffffull)
 
-#define XFP_SIGN(V)  (((V)->sign_exp >> 15) & 1)
+#define XFP_SIGN(V)  ((((V)->sign_exp >> 15) & 1) != 0)
 #define XFP_EXP(V)   ((V)->sign_exp & 0x7fff)
 #define XFP_FRAC(V)  ((V)->frac)
 

diff --git a/AltairZ80/m68k/example/m68kcpu.c b/AltairZ80/m68k/example/m68kcpu.c
@@ -1047,7 +1047,7 @@ void m68k_set_irq(unsigned int int_level)
 	/* A transition from < 7 to 7 always interrupts (NMI) */
 	/* Note: Level 7 can also level trigger like a normal IRQ */
 	if(old_level != 0x0700 && CPU_INT_LEVEL == 0x0700)
-		m68ki_cpu.nmi_pending = TRUE;
+		m68ki_cpu.nmi_pending = NMI_TRUE;
 }
 
 void m68k_set_virq(unsigned int level, unsigned int active)

diff --git a/AltairZ80/m68k/m68k.h b/AltairZ80/m68k/m68k.h
@@ -38,9 +38,9 @@ extern "C" {
 #define ARRAY_LENGTH(x)         (sizeof(x) / sizeof(x[0]))
 #endif
 
-#ifndef FALSE
-#define FALSE 0
-#define TRUE 1
+#ifndef NMI_FALSE
+#define NMI_FALSE 0
+#define NMI_TRUE 1
 #endif
 
 /* ======================================================================== */

diff --git a/AltairZ80/m68k/m68kcpu.c b/AltairZ80/m68k/m68kcpu.c
@@ -1047,7 +1047,7 @@ void m68k_set_irq(unsigned int int_level)
     /* A transition from < 7 to 7 always interrupts (NMI) */
     /* Note: Level 7 can also level trigger like a normal IRQ */
     if(old_level != 0x0700 && CPU_INT_LEVEL == 0x0700)
-        m68ki_cpu.nmi_pending = TRUE;
+        m68ki_cpu.nmi_pending = NMI_TRUE;
 }
 
 void m68k_set_virq(unsigned int level, unsigned int active)

diff --git a/AltairZ80/m68k/m68kcpu.h b/AltairZ80/m68k/m68kcpu.h
@@ -2136,7 +2136,7 @@ static inline void m68ki_check_interrupts(void)
 {
     if(m68ki_cpu.nmi_pending)
     {
-        m68ki_cpu.nmi_pending = FALSE;
+        m68ki_cpu.nmi_pending = NMI_FALSE;
         m68ki_exception_interrupt(7);
     }
     else if(CPU_INT_LEVEL > FLAG_INT_MASK)

diff --git a/AltairZ80/m68k/softfloat/milieu.h b/AltairZ80/m68k/softfloat/milieu.h
@@ -38,5 +38,5 @@ these four paragraphs for those parts of this code that are retained.
 /*----------------------------------------------------------------------------
 | Symbolic Boolean literals.
 *----------------------------------------------------------------------------*/
-#define FALSE 0
-#define TRUE 1
+#define NMI_FALSE 0
+#define NMI_TRUE 1
diff --git a/AltairZ80/s100_dazzler.c b/AltairZ80/s100_dazzler.c
@@ -63,10 +63,10 @@
 */
 VID_DISPLAY *daz_vptr = NULL;
 
-static t_bool daz_0e = 0x00;
-static t_bool daz_0f = 0x80;
+static uint8 daz_0e = 0x00;
+static uint8 daz_0f = 0x80;
 static uint32 daz_addr = 0x0000;
-static t_bool daz_frame = 0x3f;
+static uint8 daz_frame = 0x3f;
 static uint8 daz_res = 32;
 static uint16 daz_pages = 1;
 static uint16 daz_window_width = 640;

diff --git a/H316/h316_hi.c b/H316/h316_hi.c
@@ -784,7 +784,7 @@ t_stat hi_attach (UNIT *uptr, CONST char *cptr)
   //    ATTACH HIn llll:w.x.y.z:rrrr - connect via UDP to a remote simh host
   //
   t_stat ret;  char *pfn;  uint16 host = uptr->hline;
-  t_bool fport = sim_switches & SWMASK('P');
+  t_bool fport = ((sim_switches & SWMASK('P')) != 0);
 
   // If we're already attached, then detach ...
   if ((uptr->flags & UNIT_ATT) != 0) detach_unit(uptr);

diff --git a/H316/h316_mi.c b/H316/h316_mi.c
@@ -694,7 +694,7 @@ t_stat mi_attach (UNIT *uptr, CONST char *cptr)
   //    ATTACH MIn llll:w.x.y.z:rrrr - connect via UDP to a remote simh host
   //
   t_stat ret;  char *pfn;  uint16 line = uptr->mline;
-  t_bool fport = sim_switches & SWMASK('P');
+  t_bool fport = ((sim_switches & SWMASK('P')) != 0);
 
   // If we're already attached, then detach ...
   if ((uptr->flags & UNIT_ATT) != 0) detach_unit(uptr);

diff --git a/HP2100/hp2100_defs.h b/HP2100/hp2100_defs.h
@@ -740,8 +740,8 @@ typedef enum {                                  /* poll synchronization modes */
 /* Flip-flops */
 
 typedef enum {                                  /* flip-flop values */
-    CLEAR = 0,                                  /*   the flip-flop is clear */
-    SET   = 1                                   /*   the flip-flop is set */
+    CLEAR = FALSE,                              /*   the flip-flop is clear */
+    SET   = TRUE                                /*   the flip-flop is set */
     } FLIP_FLOP;
 
 

diff --git a/HP2100/hp2100_sys.c b/HP2100/hp2100_sys.c
@@ -4153,7 +4153,7 @@ switch (op_type) {                                      /* dispatch by the opera
 
     case opSCHC:
     case opSCOHC:
-        clear = (instruction & IR_HCF);                 /* set TRUE if the clear-flag bit is set */
+        clear = (instruction & IR_HCF) != 0;            /* set TRUE if the clear-flag bit is set */
 
     /* fall through into the opSC case */
 

diff --git a/HP3000/hp3000_lp.c b/HP3000/hp3000_lp.c
@@ -1718,10 +1718,11 @@ return IORETURN (outbound_signals, outbound_value);     /* return the outbound s
 static t_stat xfer_service (UNIT *uptr)
 {
 static t_bool device_flag_last = FALSE;
+const t_bool device_cmd_bool = (device_command ^ J2W10_INSTALLED) != 0;
 t_stat        result;
 OUTBOUND_SET  signals;
 
-device_command_out = device_command ^ J2W10_INSTALLED;  /* set device command out; invert if W10 is installed */
+device_command_out = device_cmd_bool;                   /* set device command out; invert if W10 is installed */
 
 if (lp_dev.flags & DEV_DIAG)                            /* if the DHA is connected */
     result = diag_service (uptr);                       /*   then service the diagnostic hardware */

diff --git a/I1401/i1401_cd.c b/I1401/i1401_cd.c
@@ -98,7 +98,7 @@
 
 extern uint8 M[];
 extern int32 ind[64], ssa, iochk;
-extern int32 conv_old;
+extern t_bool conv_old;
 
 int32 s1sel, s2sel, s4sel, s8sel;
 char cdr_buf[(2 * CBUFSIZE) + 1];                       /* > CDR_WIDTH */

diff --git a/I1401/i1401_cpu.c b/I1401/i1401_cpu.c
@@ -206,7 +206,7 @@ int32 iochk = 0;                                        /* I/O check stop */
 int32 hst_p = 0;                                        /* history pointer */
 int32 hst_lnt = 0;                                      /* history length */
 InstHistory *hst = NULL;                                /* instruction history */
-t_bool conv_old = 0;                                    /* old conversions */
+t_bool conv_old = FALSE;                                /* old conversions */
 
 extern int32 sim_emax;
 
@@ -1954,7 +1954,7 @@ return SCPE_OK;
 
 t_stat cpu_set_conv (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
-conv_old = val;
+conv_old = (val != 0);
 return SCPE_OK;
 }
 

diff --git a/I1401/i1401_iq.c b/I1401/i1401_iq.c
@@ -87,7 +87,7 @@ DEVICE inq_dev = {
 t_stat inq_io (int32 flag, int32 mod)
 {
 int32 i, t, wm_seen = 0;
-t_bool use_h = inq_unit.flags & UNIT_PCH;
+t_bool use_h = ((inq_unit.flags & UNIT_PCH) != 0);
 
 ind[IN_INC] = 0;                                        /* clear inq clear */
 switch (mod) {                                          /* case on mod */

diff --git a/I1401/i1401_sys.c b/I1401/i1401_sys.c
@@ -200,7 +200,7 @@ return;
 t_stat dcw (FILE *of, int32 op, t_value *val, int32 sw)
 {
 int32 i;
-t_bool use_h = sw & SWMASK ('F');
+t_bool use_h = (sw & SWMASK ('F')) != 0;
 
 fprintf (of, "DCW @%c", bcd2ascii (op, use_h));         /* assume it's data */
 for (i = 1; i < sim_emax; i++) {
@@ -232,7 +232,7 @@ t_stat fprint_sym (FILE *of, t_addr addr, t_value *val,
 {
 int32 op, flags, ilnt, i, t;
 int32 wmch = conv_old? '~': '`';
-t_bool use_h = sw & SWMASK ('F');
+t_bool use_h = (sw & SWMASK ('F')) != 0;
 
 if (sw & SWMASK ('C')) {                                /* character? */
     t = val[0];

diff --git a/I7094/i7094_defs.h b/I7094/i7094_defs.h
@@ -476,7 +476,7 @@ t_stat ch6_end_nds (uint32 ch);
 uint32 ch6_set_flags (uint32 ch, uint32 unit, uint32 flags);
 t_stat ch6_err_disc (uint32 ch, uint32 unit, uint32 flags);
 t_stat ch6_req_rd (uint32 ch, uint32 unit, t_uint64 val, uint32 flags);
-t_stat ch6_req_wr (uint32 ch, uint32 unit);
+t_bool ch6_req_wr (uint32 ch, uint32 unit);
 t_bool ch6_qconn (uint32 ch, uint32 unit);
 t_stat ch9_req_rd (uint32 ch, t_uint64 val);
 void ch9_set_atn (uint32 ch);

diff --git a/Ibm1130/ibm1130_cr.c b/Ibm1130/ibm1130_cr.c
@@ -723,8 +723,6 @@ static CPCODE cardcode_026C[] =     /* 026 commercial */
     {0x2220,        '('},           /* if ASCII has (, treat like % */
 };
 
-extern int cgi;
-
 static int16 ascii_to_card[256];
 
 static CPCODE *cardcode;

diff --git a/Ibm1130/ibm1130_defs.h b/Ibm1130/ibm1130_defs.h
@@ -44,8 +44,8 @@
 /* ------------------------------------------------------------------------ */
 /* Global state */
 
-extern int cgi;                             /* TRUE if we are running as a CGI program */
-extern int cgiwritable;                     /* TRUE if we can write the disk images back to the image file in CGI mode */
+extern t_bool cgi;                          /* TRUE if we are running as a CGI program */
+extern t_bool cgiwritable;                  /* TRUE if we can write the disk images back to the image file in CGI mode */
 extern t_bool sim_gui;
 
 extern uint16 M[];                          /* core memory, up to 32Kwords (note: don't even think about trying 64K) */

diff --git a/Ibm1130/ibm1130_disk.c b/Ibm1130/ibm1130_disk.c
@@ -540,7 +540,7 @@ static t_stat dsk_attach (UNIT *uptr, CONST char *cptr)
     }
 
     enable_dms_tracing(sim_switches & SWMASK('D'));
-    raw_disk_debug = sim_switches & SWMASK('G');
+    raw_disk_debug = (sim_switches & SWMASK('G')) != 0;
 
     return SCPE_OK;
 }

diff --git a/Ibm1130/ibm1130_gui.c b/Ibm1130/ibm1130_gui.c
@@ -102,7 +102,7 @@ extern int boot_drive;
 extern t_bool program_is_loaded;
 
 #ifndef GUI_SUPPORT
-    void update_gui (int force)               {}        /* stubs for non-GUI builds */
+    void update_gui (t_bool force)            {}     /* stubs for non-GUI builds */
     void forms_check (int set)                {}
     void print_check (int set)                {}
     void keyboard_select (int select)         {}
@@ -403,7 +403,7 @@ static void RepaintRegion (HWND hWnd, int left, int top, int right, int bottom)
  * reflected instantly.
  * ------------------------------------------------------------------------ */
 
-void update_gui (BOOL force)
+void update_gui (t_bool force)
 {   
     int i;
     BOOL state;

diff --git a/Ibm1130/ibm1130_sca.c b/Ibm1130/ibm1130_sca.c
@@ -675,7 +675,7 @@ static t_stat sca_svc (UNIT *uptr)
         if (timeout)
             sca_interrupt(SCA_DSW_TIMEOUT);
 
-        any_timer_running = (sca_timer_state[0]| sca_timer_state[1] | sca_timer_state[2]) & SCA_TIMER_RUNNING;
+        any_timer_running = ((sca_timer_state[0]| sca_timer_state[1] | sca_timer_state[2]) & SCA_TIMER_RUNNING) != 0;
     }
 
     if (sca_dsw & SCA_DSW_READY) {              /* if connected */
@@ -1003,7 +1003,7 @@ void xio_sca (int32 iocc_addr, int32 func, int32 modify)
                 sca_toggle_timer(TIMER_3S, msec_now);           /* toggle the 3 sec and 1.35 sec timers accordingly */
                 sca_toggle_timer(TIMER_125S, msec_now);
 
-                any_timer_running = (sca_timer_state[0]| sca_timer_state[1] | sca_timer_state[2]) & SCA_TIMER_RUNNING;
+                any_timer_running = ((sca_timer_state[0]| sca_timer_state[1] | sca_timer_state[2]) & SCA_TIMER_RUNNING) != 0;
             }
 
             if (modify & 0x10) {                    /* bit 11 */

diff --git a/Ibm1130/ibm1130_stddev.c b/Ibm1130/ibm1130_stddev.c
@@ -112,8 +112,6 @@ typedef struct tag_os_map {                 /* os_map = overstrike mapping */
     unsigned char inlist[MAX_OS_CHARS];     /* inlist = overstruck ASCII characters, sorted. NOT NULL TERMINATED */
 } OS_MAP;
 
-extern int cgi;
-
 static int32 tti_dsw = 0;                   /* device status words */
 static int32 tto_dsw = 0;
        int32 con_dsw = 0;

diff --git a/Interdata/id_idc.c b/Interdata/id_idc.c
@@ -223,7 +223,7 @@ t_stat idc_attach (UNIT *uptr, CONST char *cptr);
 t_stat idc_set_size (UNIT *uptr, int32 val, CONST char *cptr, void *desc);
 void idc_wd_byte (uint32 dat);
 t_stat idc_rds (UNIT *uptr);
-t_stat idc_wds (UNIT *uptr);
+t_bool idc_wds (UNIT *uptr);
 t_bool idc_dter (UNIT *uptr, uint32 first);
 void idc_done (uint32 flg);
 

diff --git a/ND100/nd100_sys.c b/ND100/nd100_sys.c
@@ -94,7 +94,7 @@ gw(FILE *f)
  */
 
 t_stat
-sim_load(FILE *f, CONST char *buf, CONST char *fnam, t_bool flag)
+sim_load(FILE *f, CONST char *buf, CONST char *fnam, int flag)
 {
         int B, C, E, F, H, I;
         int w, i, rv;

diff --git a/PDP10/pdp10_ksio.c b/PDP10/pdp10_ksio.c
@@ -1867,7 +1867,7 @@ return;
 
 /* Build dib_tab from device list */
 
-t_bool build_dib_tab (void)
+t_stat build_dib_tab (void)
 {
 int32 i, j, k;
 DEVICE *dptr;

diff --git a/PDP11/pdp11_cr.c b/PDP11/pdp11_cr.c
@@ -1753,7 +1753,7 @@ t_stat cr_set_eof (    UNIT    *uptr,
 {
     if (DEBUG_PRS (cr_dev))
         fprintf (sim_deb, "set_eof\n");
-    eofPending = 1;
+    eofPending = TRUE;
 
     return (SCPE_OK);
 }

diff --git a/PDP11/pdp11_rq.c b/PDP11/pdp11_rq.c
@@ -3230,7 +3230,7 @@ t_stat rq_attach (UNIT *uptr, CONST char *cptr)
 {
 MSC *cp = rq_ctxmap[uptr->cnum];
 t_stat r;
-t_bool dontchangecapac = (uptr->flags & UNIT_NOAUTO);
+t_bool dontchangecapac = ((uptr->flags & UNIT_NOAUTO) != 0);
 
 if (drv_tab[GET_DTYPE (uptr->flags)].flgs & RQDF_RO) {
     sim_switches |= SWMASK ('R');

diff --git a/SAGE/m68k_sys.c b/SAGE/m68k_sys.c
@@ -231,7 +231,7 @@ static t_stat m68k_sread(FILE* fptr)
     return SCPE_FMT;
 }
 
-t_stat sim_load(FILE* fptr, CONST char* cptr, CONST char* fnam, t_bool flag)
+t_stat sim_load(FILE* fptr, CONST char* cptr, CONST char* fnam, int flag)
 {
     int i,len,rc;
     uint16 data;

diff --git a/VAX/vax4xx_va.c b/VAX/vax4xx_va.c
@@ -1384,7 +1384,7 @@ t_stat va_set_capture (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
 if (vid_active)
     return sim_messagef (SCPE_ALATT, "Capture Mode Can't be changed with device enabled\n");
-va_input_captured = val;
+va_input_captured = (val != 0);
 return SCPE_OK;
 }
 

diff --git a/VAX/vax4xx_vc.c b/VAX/vax4xx_vc.c
@@ -544,7 +544,7 @@ t_stat vc_set_capture (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
 if (vid_active)
     return sim_messagef (SCPE_ALATT, "Capture Mode Can't be changed with device enabled\n");
-vc_input_captured = val;
+vc_input_captured = (val != 0);
 return SCPE_OK;
 }
 

diff --git a/VAX/vax780_fload.c b/VAX/vax780_fload.c
@@ -207,7 +207,7 @@ return 0;
 
 /* Read blocks */
 
-t_stat rtfile_read (uint32 block, uint32 count, uint16 *buffer)
+t_bool rtfile_read (uint32 block, uint32 count, uint16 *buffer)
 {
 uint32 i, j;
 uint32 pos;

diff --git a/VAX/vax_sysdev.c b/VAX/vax_sysdev.c
@@ -240,7 +240,7 @@ int32 cso_csr = 0;                                      /* control/status */
 int32 cmctl_reg[CMCTLSIZE >> 2] = { 0 };                /* CMCTL reg */
 int32 ka_cacr = 0;                                      /* KA655 cache ctl */
 int32 ka_bdr = BDR_BRKENB;                              /* KA655 boot diag */
-t_bool ka_hltenab = 1;                                  /* Halt Enable / Autoboot flag */
+t_bool ka_hltenab = TRUE;                               /* Halt Enable / Autoboot flag */
 int32 ssc_base = SSCBASE;                               /* SSC base */
 int32 ssc_cnf = 0;                                      /* SSC conf */
 int32 ssc_bto = 0;                                      /* SSC timeout */
@@ -249,7 +249,7 @@ int32 tmr_csr[2] = { 0 };                               /* SSC timers */
 uint32 tmr_tir[2] = { 0 };                              /* curr interval */
 uint32 tmr_tnir[2] = { 0 };                             /* next interval */
 int32 tmr_tivr[2] = { 0 };                              /* vector */
-t_bool tmr_inst[2] = { 0 };                             /* wait instructions vs usecs */
+t_bool tmr_inst[2] = { FALSE, FALSE };                  /* wait instructions vs usecs */
 int32 ssc_adsm[2] = { 0 };                              /* addr strobes */
 int32 ssc_adsk[2] = { 0 };
 int32 cdg_dat[CDASIZE >> 2];                            /* cache data */
@@ -1733,7 +1733,7 @@ return SCPE_OK;
 
 t_stat sysd_set_halt (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
-ka_hltenab = val;
+ka_hltenab = (val != 0);
 if (ka_hltenab)
     ka_bdr |= BDR_BRKENB;
 else

diff --git a/VAX/vax_va.c b/VAX/vax_va.c
@@ -1198,7 +1198,7 @@ t_stat va_set_capture (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
 if (vid_active)
     return sim_messagef (SCPE_ALATT, "Capture Mode Can't be changed with device enabled\n");
-va_input_captured = val;
+va_input_captured = (val != 0);
 return SCPE_OK;
 }
 

diff --git a/VAX/vax_vc.c b/VAX/vax_vc.c
@@ -1079,7 +1079,7 @@ t_stat vc_set_capture (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
 if (vid_active)
     return sim_messagef (SCPE_ALATT, "Capture Mode Can't be changed with device enabled\n");
-vc_input_captured = val;
+vc_input_captured = (val != 0);
 return SCPE_OK;
 }