diff --git a/Firmware/optiboot_w25x20cl.cpp b/Firmware/optiboot_w25x20cl.cpp
index e84bf639..584c32fe 100644
--- a/Firmware/optiboot_w25x20cl.cpp
+++ b/Firmware/optiboot_w25x20cl.cpp
@@ -258,11 +258,11 @@ void optiboot_w25x20cl_enter()
         uint32_t addr = (((uint32_t)rampz) << 16) | address;
         // During a single bootloader run, only erase a 64kB block once.
         // An 8bit bitmask 'pages_erased' covers 512kB of FLASH memory.
-        if (address == 0 && (pages_erased & (1 << addr)) == 0) {
+        if ((address == 0) && (pages_erased & (1 << (addr >> 16))) == 0) {
           w25x20cl_wait_busy();
           w25x20cl_enable_wr();
           w25x20cl_block64_erase(addr);
-          pages_erased |= (1 << addr);
+          pages_erased |= (1 << (addr >> 16));
         }
         w25x20cl_wait_busy();
         w25x20cl_enable_wr();
diff --git a/lang/lang_en_cz.txt b/lang/lang_en_cz.txt
index 0fc920ad..230055b1 100755
--- a/lang/lang_en_cz.txt
+++ b/lang/lang_en_cz.txt
@@ -1188,7 +1188,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"Tiskarna zacne tisknout lomenou caru. Otacenim tlacitka nastavte optimalni vysku. Postupujte podle obrazku v handbooku (kapitola Kalibrace)."
 
 #
 "Y-correct:"
diff --git a/lang/lang_en_de.txt b/lang/lang_en_de.txt
index 91107d8e..11c36b40 100755
--- a/lang/lang_en_de.txt
+++ b/lang/lang_en_de.txt
@@ -1188,7 +1188,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"Der Drucker beginnt mit dem Drucken einer Zickzacklinie. Drehen Sie den Knopf, bis Sie die optimale Hoehe erreicht haben. Ueberpruefen Sie die Bilder im Handbuch (Kapitel Kalibrierung)."
 
 #
 "Y-correct:"
diff --git a/lang/lang_en_es.txt b/lang/lang_en_es.txt
index 56539966..8255bd79 100755
--- a/lang/lang_en_es.txt
+++ b/lang/lang_en_es.txt
@@ -1188,7 +1188,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"La impresora comenzara a imprimir una linea en zig-zag. Gira el dial hasta que la linea alcance la altura optima. Mira las fotos del manual (Capitulo de calibracion)."
 
 #
 "Y-correct:"
diff --git a/lang/lang_en_fr.txt b/lang/lang_en_fr.txt
index b0b62e9d..f6add948 100755
--- a/lang/lang_en_fr.txt
+++ b/lang/lang_en_fr.txt
@@ -1185,7 +1185,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"L'imprimante commencera a  imprimer une ligne en zig-zag. Tournez le bouton jusqu'a atteindre la hauteur optimale. Consultez les photos dans le manuel (chapitre Calibration)."
 
 #
 "Y-correct:"
diff --git a/lang/lang_en_it.txt b/lang/lang_en_it.txt
index 44285a43..672859a0 100755
--- a/lang/lang_en_it.txt
+++ b/lang/lang_en_it.txt
@@ -1187,7 +1187,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"La stampante iniziera a stampare una linea a zig-zag. Gira la manopola fino a che non hai raggiungo l'altezza ottimale. Verifica con le immagini nel manuale (capitolo sulla calibrazione):"
 
 #
 "Y-correct:"
diff --git a/lang/lang_en_pl.txt b/lang/lang_en_pl.txt
index 25c4d14f..aa07cd75 100755
--- a/lang/lang_en_pl.txt
+++ b/lang/lang_en_pl.txt
@@ -1187,7 +1187,7 @@
 
 #
 "The printer will start printing a zig-zag line. Rotate the knob until you reach the optimal height. Check the pictures in the handbook (Calibration chapter)."
-"\x00"
+"Drukarka zacznie drukowanie linii w ksztalcie zygzaka. Ustaw optymalna wysokosc obracajac pokretlo. Porownaj z ilustracjami w Podreczniku (rozdzial Kalibracja)."
 
 #
 "Y-correct:"