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diff --git a/pat80-computer/hardware/fritzing/pato.fzz b/pat80-computer/hardware/fritzing/pato.fzz
new file mode 100644
index 0000000..0b7d2dd
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diff --git a/pat80-computer/hardware/schematics/pat80/pat80-cache.lib b/pat80-computer/hardware/schematics/pat80/pat80-cache.lib
index 67d6ed5..dae2018 100644
--- a/pat80-computer/hardware/schematics/pat80/pat80-cache.lib
+++ b/pat80-computer/hardware/schematics/pat80/pat80-cache.lib
@@ -1,6 +1,79 @@
 EESchema-LIBRARY Version 2.4
 #encoding utf-8
 #
+# 74xx_74LS32
+#
+DEF 74xx_74LS32 U 0 40 Y Y 5 L N
+F0 "U" 0 50 50 H V C CNN
+F1 "74xx_74LS32" 0 -50 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ DIP?14*
+$ENDFPLIST
+DRAW
+A -360 0 258 354 -354 1 1 10 N -150 150 -150 -150
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+ENDDRAW
+ENDDEF
+#
 # CPU_Z80CPU
 #
 DEF CPU_Z80CPU U 0 40 Y Y 1 F N
@@ -57,6 +130,41 @@ X D5 9 700 -1000 150 L 50 50 1 1 B
 ENDDRAW
 ENDDEF
 #
+# Device_C
+#
+DEF Device_C C 0 10 N Y 1 F N
+F0 "C" 25 100 50 H V L CNN
+F1 "Device_C" 25 -100 50 H V L CNN
+F2 "" 38 -150 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ C_*
+$ENDFPLIST
+DRAW
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+X ~ 1 0 150 110 D 50 50 1 1 P
+X ~ 2 0 -150 110 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Device_R
+#
+DEF Device_R R 0 0 N Y 1 F N
+F0 "R" 80 0 50 V V C CNN
+F1 "Device_R" 0 0 50 V V C CNN
+F2 "" -70 0 50 V I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ R_*
+$ENDFPLIST
+DRAW
+S -40 -100 40 100 0 1 10 N
+X ~ 1 0 150 50 D 50 50 1 1 P
+X ~ 2 0 -150 50 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
 # Memory_EEPROM_28C256
 #
 DEF Memory_EEPROM_28C256 U 0 20 Y Y 1 F N
@@ -101,4 +209,48 @@ X A1 9 -400 800 100 R 50 50 1 1 I
 ENDDRAW
 ENDDEF
 #
+# Switch_SW_Push
+#
+DEF Switch_SW_Push SW 0 40 N N 1 F N
+F0 "SW" 50 100 50 H V L CNN
+F1 "Switch_SW_Push" 0 -60 50 H V C CNN
+F2 "" 0 200 50 H I C CNN
+F3 "" 0 200 50 H I C CNN
+DRAW
+C -80 0 20 0 1 0 N
+C 80 0 20 0 1 0 N
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+P 2 0 1 0 100 50 -100 50 N
+X 1 1 -200 0 100 R 50 50 0 1 P
+X 2 2 200 0 100 L 50 50 0 1 P
+ENDDRAW
+ENDDEF
+#
+# power_GND
+#
+DEF power_GND #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 0 -250 50 H I C CNN
+F1 "power_GND" 0 -150 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+DRAW
+P 6 0 1 0 0 0 0 -50 50 -50 0 -100 -50 -50 0 -50 N
+X GND 1 0 0 0 D 50 50 1 1 W N
+ENDDRAW
+ENDDEF
+#
+# power_VCC
+#
+DEF power_VCC #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 0 -150 50 H I C CNN
+F1 "power_VCC" 0 150 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+DRAW
+C 0 75 25 0 1 0 N
+P 2 0 1 0 0 0 0 50 N
+X VCC 1 0 0 0 U 50 50 1 1 W N
+ENDDRAW
+ENDDEF
+#
 #End Library
diff --git a/pat80-computer/hardware/schematics/pat80/pat80.sch b/pat80-computer/hardware/schematics/pat80/pat80.sch
index f2d561f..65d0faa 100644
--- a/pat80-computer/hardware/schematics/pat80/pat80.sch
+++ b/pat80-computer/hardware/schematics/pat80/pat80.sch
@@ -1,7 +1,7 @@
 EESchema Schematic File Version 4
 EELAYER 30 0
 EELAYER END
-$Descr A4 11693 8268
+$Descr A3 16535 11693
 encoding utf-8
 Sheet 1 1
 Title ""
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 Comment3 ""
 Comment4 ""
 $EndDescr
-Text Notes 7400 7500 0    50   ~ 0
+Text Notes 12250 10950 0    79   ~ 0
 Pat80 Z80 home computer
-Text Notes 8150 7650 0    50   ~ 0
+Text Notes 13000 11050 0    50   ~ 0
 2021-03-15
 $Comp
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-U 1 1 604F040E
-P 3150 2650
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-F 1 "Z80CPU" H 3150 4240 50  0000 C CNN
-F 2 "" H 3150 3050 50  0001 C CNN
-F 3 "www.zilog.com/manage_directlink.php?filepath=docs/z80/um0080" H 3150 3050 50  0001 C CNN
-	1    3150 2650
-	1    0    0    -1  
-$EndComp
-$Comp
 L Memory_EEPROM:28C256 U3
 U 1 1 604F6B81
-P 6850 1700
-F 0 "U3" V 6896 556 50  0000 R CNN
-F 1 "256k (32k x 8) EEPROM" V 6805 556 50  0000 R CNN
-F 2 "" H 6850 1700 50  0001 C CNN
-F 3 "http://ww1.microchip.com/downloads/en/DeviceDoc/doc0006.pdf" H 6850 1700 50  0001 C CNN
-	1    6850 1700
+P 6900 2000
+F 0 "U3" V 6946 856 50  0000 R CNN
+F 1 "256k (32k x 8) EEPROM" V 6855 856 50  0000 R CNN
+F 2 "" H 6900 2000 50  0001 C CNN
+F 3 "http://ww1.microchip.com/downloads/en/DeviceDoc/doc0006.pdf" H 6900 2000 50  0001 C CNN
+	1    6900 2000
 	0    -1   -1   0   
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diff --git a/pat80-computer/hardware/schematics/pat80/pat80.sch-bak b/pat80-computer/hardware/schematics/pat80/pat80.sch-bak
index 19e75c4..3f2a4c4 100644
--- a/pat80-computer/hardware/schematics/pat80/pat80.sch-bak
+++ b/pat80-computer/hardware/schematics/pat80/pat80.sch-bak
@@ -18,28 +18,6 @@ Pat80 Z80 home computer
 Text Notes 8150 7650 0    50   ~ 0
 2021-03-15
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+F 3 "www.zilog.com/manage_directlink.php?filepath=docs/z80/um0080" H 3150 3050 50  0001 C CNN
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+$EndComp
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+L power:VCC #PWR?
+U 1 1 6050EE1E
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+$EndComp
+$Comp
+L 74xx:74LS32 U?
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+F 2 "" H 1700 1450 50  0001 C CNN
+F 3 "http://www.ti.com/lit/gpn/sn74LS32" H 1700 1450 50  0001 C CNN
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+$EndComp
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+L Switch:SW_Push SW1
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+F 3 "" H 950 1950 50  0001 C CNN
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+$EndComp
+$Comp
+L Device:C C?
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+F 3 "~" H 1300 1750 50  0001 C CNN
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+$EndComp
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+Wire Wire Line
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+L power:VCC #PWR?
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+$EndComp
+$Comp
+L power:GND #PWR?
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+L Device:C C?
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+F 2 "" H 3588 500 50  0001 C CNN
+F 3 "~" H 3550 650 50  0001 C CNN
+	1    3550 650 
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+$Comp
+L Device:C C?
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+F 3 "~" H 3550 850 50  0001 C CNN
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+L power:GND #PWR?
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+F 3 "" H 3800 750 50  0001 C CNN
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+$EndComp
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+Connection ~ 3700 750 
+Wire Wire Line
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+Wire Wire Line
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+	3400 850  3400 750 
+Wire Wire Line
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+Wire Wire Line
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+Connection ~ 3150 750 
+Wire Wire Line
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+Text Notes 3300 1050 0    50   ~ 0
+Smoothing caps
+Text Notes 750  2500 0    50   ~ 0
+Reset circuit with debouncing\nand power-on-reset
+$Comp
+L Device:R R?
+U 1 1 60584118
+P 950 1200
+F 0 "R?" H 1020 1246 50  0000 L CNN
+F 1 "270k" H 1020 1155 50  0000 L CNN
+F 2 "" V 880 1200 50  0001 C CNN
+F 3 "~" H 950 1200 50  0001 C CNN
+	1    950  1200
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
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+Connection ~ 950  1450
+Wire Wire Line
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 Wire Bus Line
 	6050 1100 8600 1100
 Wire Bus Line
@@ -497,5 +737,5 @@ Wire Bus Line
 Wire Bus Line
 	5100 2300 7250 2300
 Wire Bus Line
-	5100 4050 7250 4050
+	5100 3850 7250 3850
 $EndSCHEMATC
diff --git a/pat80-computer/software/z80-assembly/os/monitor.asm b/pat80-computer/software/z80-assembly/os/monitor.asm
index 71def64..9a7b594 100644
--- a/pat80-computer/software/z80-assembly/os/monitor.asm
+++ b/pat80-computer/software/z80-assembly/os/monitor.asm
@@ -27,9 +27,8 @@ MON_ARG_HEX: DB "    0x",0
 MON_HELP: DB 10,"Available commands:\nHELP prints this message\nDUMP [ADDR] shows memory content\nSET [ADDR] sets memory content\nZERO [ADDR] [ADDR] sets all bytes to 0 in the specified range\nLOAD\nRUN [ADDR] executes code starting from ADDR\nADB starts Assembly Deploy Bridge\nMEMTEST checks ram boundaries\nQUIT exits",0
 MON_MSG_ADB: DB 10,"Waiting for data.",0
 MON_ERR_SYNTAX: DB "    Syntax error",0
-MON_RAMTEST_INTRO: DB " Checking memory... ",0
-MON_RAMTEST_RAMSTART: DB " Ram starts at 0x",0
-;MON_ADB_TIMEOUT: EQU 0xFF     // Number of cycles after an ADB binary transfer is considered completed
+; MON_RAMTEST_INTRO: DB " Checking memory... ",0
+; MON_RAMTEST_RAMSTART: DB " Ram starts at 0x",0
 MON_DUMP_BYTES_LINES: EQU 8
 MON_DUMP_BYTES_PER_LINE: EQU 8
 
@@ -70,9 +69,9 @@ Monitor_main:
         ld hl, MON_COMMAND_ADB
         cp (hl)
         jp z, monitor_adb
-        ld hl, MON_COMMAND_MEMTEST
-        cp (hl)
-        jp z, monitor_memtest
+        ; ld hl, MON_COMMAND_MEMTEST
+        ; cp (hl)
+        ; jp z, monitor_memtest
         ld hl, MON_COMMAND_QUIT
 		cp (hl)
 		jp z, monitor_quit