diff --git a/README.md b/README.md
index f88603d..0e580b5 100644
--- a/README.md
+++ b/README.md
@@ -10,19 +10,21 @@ Sample Applications
 - [Space Invaders](https://github.com/jscrane/invaders)
 - [Pacman](https://github.com/jscrane/pacman)
 - [Commodore PET](https://github.com/jscrane/PET)
-- [Compukit UK101](https://github.com/jscrane/UK101)
+- [Compukit UK101](https://github.com/jscrane/UK101) and [MicroUK101](https://github.com/jscrane/UK101)
 - [Commodore Chessmate](https://github.com/jscrane/Chessmate)
 
 Configuration for Arduino
 --------------
-If building using the Arduino IDE, `r65emu/hw/user.h` must be configured correctly.
+If building using the Arduino IDE, `r65emu/src/hw/user.h` must be configured correctly.
 
 Currently the only mass-produced board which is supported is the 
 [LilyGO TTGO](https://www.tinytronics.nl/shop/en/development-boards/microcontroller-boards/with-wi-fi/lilygo-ttgo-vga32-esp32).
 
 Examples are also given for a generic `node32s` board and a homebrew `esp8bit` board.
 
-Copy your configuration file to `user.h`. If the board is also mass-produced, please open a PR to add the new file to the library.
+Copy your configuration file to `user.h`. If the board is also mass-produced, please open a 
+[PR](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/about-pull-requests)
+to add the new file to the library.
 
 Some emulations require a filesystem image containing programs to be uploaded:
 - On esp32, this [arduino plugin](https://github.com/me-no-dev/arduino-esp32fs-plugin) is required for that
diff --git a/hw/user.h b/hw/user.h
deleted file mode 100644
index 5c3e358..0000000
--- a/hw/user.h
+++ /dev/null
@@ -1,3 +0,0 @@
-// user-configured hardware description
-
-#warning "hw/user.h not configured!"
diff --git a/library.properties b/library.properties
index 04f0433..77898a4 100644
--- a/library.properties
+++ b/library.properties
@@ -7,4 +7,5 @@ paragraph=Supports 6502, 8080 and Z80 processors
 category=Other
 url=https://github.com/jscrane/r65emu
 architectures=esp32, esp8266, tivac
+depends=PS2KeyAdvanced, PS2KeyMap, PS2KeyRaw
 includes=r65emu.h
diff --git a/CPU.h b/src/CPU.h
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rename from CPU.h
rename to src/CPU.h
diff --git a/TinyFont.h b/src/TinyFont.h
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rename from TinyFont.h
rename to src/TinyFont.h
diff --git a/acia.cpp b/src/acia.cpp
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diff --git a/acia.h b/src/acia.h
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diff --git a/display.cpp b/src/display.cpp
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diff --git a/display.h b/src/display.h
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diff --git a/filer.h b/src/filer.h
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diff --git a/flash_filer.cpp b/src/flash_filer.cpp
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diff --git a/flash_filer.h b/src/flash_filer.h
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diff --git a/hardware.cpp b/src/hardware.cpp
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rename from hardware.cpp
rename to src/hardware.cpp
diff --git a/hardware.h b/src/hardware.h
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rename from hardware.h
rename to src/hardware.h
diff --git a/hw/esp8bit.h b/src/hw/esp8bit.h
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rename to src/hw/esp8bit.h
diff --git a/hw/node32s-example.h b/src/hw/node32s-example.h
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rename to src/hw/node32s-example.h
diff --git a/hw/stellarpad-example.h b/src/hw/stellarpad-example.h
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rename from hw/stellarpad-example.h
rename to src/hw/stellarpad-example.h
diff --git a/hw/ttgo-t7-v14-mini32.h b/src/hw/ttgo-t7-v14-mini32.h
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rename from hw/ttgo-t7-v14-mini32.h
rename to src/hw/ttgo-t7-v14-mini32.h
diff --git a/src/hw/user.h b/src/hw/user.h
new file mode 100644
index 0000000..83ac2f9
--- /dev/null
+++ b/src/hw/user.h
@@ -0,0 +1,11 @@
+// user-configured hardware description
+
+#warning "hw/user.h not configured!"
+
+#if defined(ARDUINO_ARCH_ESP32)
+#define RAM_SIZE        65536
+#elif defined(ARDUINO_ARCH_ESP8266)
+#define RAM_SIZE        32768
+#else
+#define RAM_SIZE        8192
+#endif
diff --git a/hw_serial_dsp.h b/src/hw_serial_dsp.h
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rename to src/hw_serial_dsp.h
diff --git a/hw_serial_kbd.cpp b/src/hw_serial_kbd.cpp
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rename to src/hw_serial_kbd.cpp
diff --git a/hw_serial_kbd.h b/src/hw_serial_kbd.h
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rename to src/hw_serial_kbd.h
diff --git a/i8080.cpp b/src/i8080.cpp
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diff --git a/i8080.h b/src/i8080.h
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diff --git a/line.h b/src/line.h
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diff --git a/ps2_raw_kbd.cpp b/src/ps2_raw_kbd.cpp
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diff --git a/ps2_serial_kbd.h b/src/ps2_serial_kbd.h
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diff --git a/r6502.cpp b/src/r6502.cpp
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diff --git a/r65emu.h b/src/r65emu.h
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diff --git a/ram.h b/src/ram.h
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diff --git a/sd_filer.cpp b/src/sd_filer.cpp
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diff --git a/serialio.h b/src/serialio.h
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diff --git a/socket_filer.cpp b/src/socket_filer.cpp
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diff --git a/spiram.cpp b/src/spiram.cpp
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diff --git a/z80.cpp b/src/z80.cpp
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diff --git a/z80.h b/src/z80.h
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