diff --git a/src/jtag3.c b/src/jtag3.c
index 5e971a28..8eed8c29 100644
--- a/src/jtag3.c
+++ b/src/jtag3.c
@@ -1252,8 +1252,10 @@ static int jtag3_initialize(PROGRAMMER * pgm, AVRPART * p)
       }
     }
 
-    // Generate 12V UPDI pulse if user asks for it and  hardware supports it
-    if(p->flags & AVRPART_HAS_UPDI && PDATA(pgm)->use_hvupdi == true && p->hvupdi_variant == 0) {
+    // Generate 12V UPDI pulse if user asks for it and hardware supports it
+    if (p->flags & AVRPART_HAS_UPDI &&
+        PDATA(pgm)->use_hvupdi == true &&
+        p->hvupdi_variant == HV_UPDI_VARIANT_0) {
       parm[0] = PARM3_UPDI_HV_SIMPLE_PULSE;
       if (jtag3_setparm(pgm, SCOPE_AVR, 3, PARM3_OPT_12V_UPDI_ENABLE, parm, 1) < 0)
         return -1;
@@ -1458,7 +1460,6 @@ static int jtag3_parseextparms(PROGRAMMER * pgm, LISTID extparms)
   LNODEID ln;
   const char *extended_param;
   int rv = 0;
-  avrdude_message(MSG_INFO, "id: %s, desc: %s, type: %s\n", ldata(lfirst(pgm->id)), pgm->desc, pgm->type);
 
   for (ln = lfirst(extparms); ln; ln = lnext(ln)) {
     extended_param = ldata(ln);
diff --git a/src/libavrdude.h b/src/libavrdude.h
index 2b87ddf1..c3e89a7e 100644
--- a/src/libavrdude.h
+++ b/src/libavrdude.h
@@ -188,6 +188,10 @@ typedef struct opcode {
 #define AVRPART_IS_AT90S1200   0x1000  /* part is an AT90S1200 (needs special treatment) */
 #define AVRPART_HAS_UPDI       0x2000  /* part has UPDI i/f (AVR8X) */
 
+#define HV_UPDI_VARIANT_0      0 /* Shared UPDI/GPIO/RESET pin, HV on UPDI pin (tinyAVR0/1/2)*/
+#define HV_UPDI_VARIANT_1      1 /* Dedicated UPDI pin, no HV (megaAVR0/AVR-Dx) */
+#define HV_UPDI_VARIANT_2      2 /* Shared UPDI pin, HV on _RESET (AVR-Ex) */
+
 #define AVR_DESCLEN 64
 #define AVR_IDLEN   32
 #define AVR_FAMILYIDLEN 7