--- a/1wire.c	Sat Jan 31 23:26:21 2015 +1030
+++ b/1wire.c	Sat Jan 31 23:27:10 2015 +1030
@@ -43,11 +43,15 @@
 static uint8_t OW_LastDiscrepancy = 0;
 static uint8_t OW_LastFamilyDiscrepancy = 0;
 
-const PROGMEM char *OWProgROM_Status[] = {
-    "OK",
-    "no HW support",
-    "Invalid params",
-    "module missing/broken"
+static const char __str1[] PROGMEM = "OK";
+static const char __str2[] PROGMEM = "no HW support";
+static const char __str3[] PROGMEM = "Invalid params";
+static const char __str4[] PROGMEM = "module missing/broken";
+PGM_P const OWProgROM_Status[] PROGMEM = {
+    __str1,
+    __str2,
+    __str3,
+    __str4
 };
 
 /*-----------------------------------------------------------------------------
@@ -306,56 +310,57 @@
 
 	    /* check for no devices on 1-wire */
 	    if (bit_test == 3) {
+		/* 11 */
 		OWPRINTFP(PSTR("bit_test = %d\r\n"), bit_test);
-		return(OW_BADWIRE);
+		return(OW_NOMODULES);
 	    }
+	    /* all devices coupled have 0 or 1 */
+	    if (bit_test != 0)
+		/* 10 or 01 */
+		search_direction = !(bit_test & 0x01);  /* bit write value for search */
 	    else {
-		/* all devices coupled have 0 or 1 */
-		if (bit_test > 0)
-		    search_direction = !(bit_test & 0x01);  /* bit write value for search */
-		else {
-		    /* if this discrepancy is before the Last Discrepancy
-		     * on a previous OWNext then pick the same as last time */
-		    if (bit_number < OW_LastDiscrepancy)
-			search_direction = ((ROM[rom_byte_number] & rom_byte_mask) > 0);
-		    else
-			/* if equal to last pick 1, if not then pick 0 */
-			search_direction = (bit_number == OW_LastDiscrepancy);
+		/* 00 */
+		/* if this discrepancy is before the Last Discrepancy
+		 * on a previous OWNext then pick the same as last time */
+		if (bit_number < OW_LastDiscrepancy)
+		    search_direction = (ROM[rom_byte_number] & rom_byte_mask) > 0;
+		else
+		    /* if equal to last pick 1, if not then pick 0 */
+		    search_direction = bit_number == OW_LastDiscrepancy;
 
-		    /* if 0 was picked then record its position in LastZero */
-		    if (search_direction == 0) {
-			last_zero = bit_number;
+		/* if 0 was picked then record its position in LastZero */
+		if (search_direction == 0) {
+		    last_zero = bit_number;
 
-			/* check for Last discrepancy in family */
-			if (last_zero < 9)
-			    OW_LastFamilyDiscrepancy = last_zero;
-		    }
+		    /* check for Last discrepancy in family */
+		    if (last_zero < 9)
+			OW_LastFamilyDiscrepancy = last_zero;
 		}
+	    }
 
-		/* set or clear the bit in the ROM byte rom_byte_number
-		 * with mask rom_byte_mask */
-		if (search_direction == 1)
-		    ROM[rom_byte_number] |= rom_byte_mask;
-		else
-		    ROM[rom_byte_number] &= ~rom_byte_mask;
+	    /* set or clear the bit in the ROM byte rom_byte_number
+	     * with mask rom_byte_mask */
+	    if (search_direction == 1)
+		ROM[rom_byte_number] |= rom_byte_mask;
+	    else
+		ROM[rom_byte_number] &= ~rom_byte_mask;
 
-		/* serial number search direction write bit */
-		OWWriteBit(search_direction);
+	    /* serial number search direction write bit */
+	    OWWriteBit(search_direction);
 
-		/* increment the byte counter bit_number
-		 * and shift the mask rom_byte_mask */
-		bit_number++;
-		rom_byte_mask <<= 1;
+	    /* increment the byte counter bit_number
+	     * and shift the mask rom_byte_mask */
+	    bit_number++;
+	    rom_byte_mask <<= 1;
 
-		/* if the mask is 0 then go to new ROM byte rom_byte_number
-		 * and reset mask */
-		if (rom_byte_mask == 0) {
-		    OWCRC(ROM[rom_byte_number], &crcaccum);  /* accumulate the CRC */
-		    lastcrc8 = crcaccum;
+	    /* if the mask is 0 then go to new ROM byte rom_byte_number
+	     * and reset mask */
+	    if (rom_byte_mask == 0) {
+		OWCRC(ROM[rom_byte_number], &crcaccum);  /* accumulate the CRC */
+		lastcrc8 = crcaccum;
 		  
-		    rom_byte_number++;
-		    rom_byte_mask = 1;
-		}
+		rom_byte_number++;
+		rom_byte_mask = 1;
 	    }
 	} while (rom_byte_number < 8);  /* loop until through all ROM bytes 0-7 */
 
@@ -389,7 +394,7 @@
 
 }
 
-uint8_t PROGMEM dscrc_table[] = { 
+const uint8_t dscrc_table[] PROGMEM = {
     0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
     157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
     35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
@@ -508,13 +513,8 @@
 
 	tmp = OWReadByte();
 
-	/* Check the bits we turned off are off */
-/*
-        for (i = 0; i < 8; i++)
-	    if (!(data[i] & 1 << i) && (tmp & 1 << i))
-	        return(-3);
-*/
-	if ((!data[i] & tmp) != 0) {
+	/* Verify */
+	if (data[i] != tmp) {
 	    cons_putsP(PSTR("Readback mismatch "));
 	    cons_puts_hex(data[i]);
 	    cons_putsP(PSTR(" vs "));