diff --git a/.doxygen_config b/.doxygen_config
index 3df9fd4..9efb390 100644
--- a/.doxygen_config
+++ b/.doxygen_config
@@ -294,7 +294,7 @@ ALIASES                = "modifies=\par Modifies Registers^^" \
                          "macro=\qualifier macro \brief" \
                          "function=\qualifier subroutine \brief" \
                          "module=\file ^^ \brief" \
-                         "clock_dependant=\xrefitem clock_dependant \"Clock Speed Dependance\" \"Clock frequency dependant code\"" 
+                         "clock_dependent=\xrefitem clock_dependant \"Clock Speed Dependence\" \"Clock speed dependent code\"" 
 
 # Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C sources
 # only. Doxygen will then generate output that is more tailored for C. For
diff --git a/.extra_docs.s65 b/.extra_docs.s65
index f726379..ad2c1cb 100644
--- a/.extra_docs.s65
+++ b/.extra_docs.s65
@@ -65,3 +65,8 @@
 ;;
 ;;********************************************************************************
 
+;;********************************************************************************
+;; @defgroup system
+;; @brief Core code
+;;
+;;********************************************************************************
diff --git a/programs/memcopy.s65 b/programs/memcopy.s65
index b1b877c..298c152 100644
--- a/programs/memcopy.s65
+++ b/programs/memcopy.s65
@@ -11,7 +11,7 @@ INCLUDE_MEMCOPY = 1
 ;; @param ARG0-1: Source address
 ;; @param ARG2-3: Target address
 ;; @param Y: Number of bytes to copy
-;; @modifies: A,Y
+;; @modifies A,Y
 ;;********************************************************************************
 .proc memcopy
     cpy #0
@@ -31,7 +31,7 @@ INCLUDE_MEMCOPY = 1
 ;; @param ARG0-1: Source address
 ;; @param ARG2-3: Target address
 ;; @param ARG5-6: Number of bytes to copy (LE)
-;; @modifies: A,Y
+;; @modifies A,Y
 ;;********************************************************************************
 .proc memcopy16
     lda ARG6
diff --git a/programs/print_slow.s65 b/programs/print_slow.s65
index 087ad52..9197c94 100644
--- a/programs/print_slow.s65
+++ b/programs/print_slow.s65
@@ -10,7 +10,7 @@
 ;; @param ARG0-1: Address of the string to print
 ;; @param x: time to sleep in centiseconds
 ;; @ingroup applications
-;; @clock_dependant
+;; @clock_dependent
 ;;********************************************************************************
 .proc print_slow
     ldy #$00
diff --git a/programs/ps2_keyboard_simple_handler.s65 b/programs/ps2_keyboard_simple_handler.s65
index a99e3f5..a52156b 100644
--- a/programs/ps2_keyboard_simple_handler.s65
+++ b/programs/ps2_keyboard_simple_handler.s65
@@ -9,7 +9,7 @@ scancode:               .res 1
 ;;********************************************************************************
 ;; @function Initialize the keyboard handler
 ;; @returns Z: Z = 1 => success, Z = 0 => failure
-;; @details:
+;; @details
 ;;  Initializes the PS/2 keyboard driver and the handler.
 ;;  If any PS/2 command fails, init returns with Z = 0. The failed command (and parameter) can be loaded from `ps2kb::send_cmd` and `ps2kb::send_data`
 ;;  After init, the keyboard will be able to send scancodes.
diff --git a/programs/ps2_keyboard_text_handler.s65 b/programs/ps2_keyboard_text_handler.s65
index 1102b1a..e14ac9e 100644
--- a/programs/ps2_keyboard_text_handler.s65
+++ b/programs/ps2_keyboard_text_handler.s65
@@ -19,7 +19,7 @@ keycode:                .res 1
 ;;********************************************************************************
 ;; @function Initialize the keyboard handler
 ;; @returns Z: Z = 1 => success, Z = 0 => failure
-;; @details:
+;; @details
 ;;  Initializes the PS/2 keyboard driver and the handler.
 ;;  If any PS/2 command fails, init returns with Z = 0. The failed command (and parameter) can be loaded from `ps2kb::send_cmd` and `ps2kb::send_data`
 ;;  After init, the keyboard will be able to send scancodes.
@@ -232,7 +232,7 @@ update_leds:
 ;; @details
 ;;  Unset modifier bits if a mod key is released.
 ;; @param X: The scancode
-;; @modifies: 
+;; @modifies 
 ;;********************************************************************************
 .proc break_key
     ; rmb kb::PREVIOUS::BREAK, kb::previous_scancode 
diff --git a/programs/sleep.s65 b/programs/sleep.s65
index ace5cee..2718697 100644
--- a/programs/sleep.s65
+++ b/programs/sleep.s65
@@ -9,9 +9,9 @@
 ;; @details
 ;;   Interrupts might change the actual time to finish
 ;;   To be exact, time_cs is in units of 0.010244s
-;; @modifies: ARG15
+;; @modifies ARG15
 ;; @ingroup applications 
-;; @clock_dependant
+;; @clock_dependent
 ;;********************************************************************************
 .proc sleep
 _VAR_1 = ARG15
diff --git a/spicode.s65 b/spicode.s65
index 5fa6cda..57e8eeb 100644
--- a/spicode.s65
+++ b/spicode.s65
@@ -1,6 +1,6 @@
 ;;********************************************************************************
 ;; @file
-;; @details:
+;; @details
 ;;  This code is loaded to the computer via a SPI interface
 ;;  Currently, it must be loaded to $5000, where the main loop will begin
 ;;********************************************************************************
diff --git a/system/buffer.h65 b/system/buffer.h65
index 5cccb5c..e530ace 100644
--- a/system/buffer.h65
+++ b/system/buffer.h65
@@ -1,16 +1,20 @@
-;********************************************************************************
-; @module ringbuffer
-; @type utility
-; @details
-;   Size of the ringbuffer is RBUF_MEM_END - RBUF_MEM_START - 2, since two bytes
-;   are used by the read and write pointer
-;   The RBUF_NAME variable must be defined, the functions will then be exported
-;   as rb_<RBUF_NAME>_<function> where <function> = init, read or write
-; @requires
-;   RBUF_MEM_START: First address of ringbuffer memory space
-;   RBUF_MEM_END: Last address of ringbuffer memory space
-;   RBUF_NAME: Name of the ringbuffer
-;********************************************************************************
+;;********************************************************************************
+;; @module ringbuffer
+;; @details
+;;   Size of the ringbuffer is RBUF_MEM_END - RBUF_MEM_START - 2, since two bytes
+;;   are used by the read and write pointer
+;;   The `RBUF_NAME` variable must be defined, the functions will then be exported
+;;   as `rb_<RBUF_NAME>_<function>` where `<function>` = `init`, `read` or `write`
+;;   
+;; @note 
+;;  Doxygen can not generate proper documentation for this module, because
+;;  all names are defined using macros
+;; @requires
+;;   RBUF_MEM_START: First address of ringbuffer memory space
+;;   RBUF_MEM_END: Last address of ringbuffer memory space
+;;   RBUF_NAME: Name of the ringbuffer
+;; @ingroup utility
+;;********************************************************************************
 .code
 
 .ifndef RBUF_MEM_START
@@ -36,9 +40,9 @@ RB_LENGTH   = RBUF_MEM_END - RBUF_MEM_START - 2
 .endif
 
 
-;********************************************************************************
-; @function Initialize the buffer
-;********************************************************************************
+;;********************************************************************************
+;; @function Initialize the buffer
+;;********************************************************************************
 .ident(.concat(_RBUF_NAME, "_init")):
 .scope
     stz RB_WRITE
@@ -46,13 +50,13 @@ RB_LENGTH   = RBUF_MEM_END - RBUF_MEM_START - 2
     rts
 .endscope
 
-;********************************************************************************
-; @function Read a value from the buffer
-; @details
-;   If there is no value to be read, the Pz will be set
-; @returns A: value
-; @modifies: A, X
-;********************************************************************************
+;;********************************************************************************
+;; @function Read a value from the buffer
+;; @details
+;;   If there is no value to be read, the Pz will be set
+;; @returns A: value
+;; @modifies A, X
+;;********************************************************************************
 .ident(.concat(_RBUF_NAME, "_read")):
 .scope
     ldx RB_READ
@@ -72,11 +76,11 @@ RB_LENGTH   = RBUF_MEM_END - RBUF_MEM_START - 2
     rts
 .endscope
 
-;********************************************************************************
-; @function Write a value to the buffer
-; @param A: value to store
-; @modifies: X
-;********************************************************************************
+;;********************************************************************************
+;; @function Write a value to the buffer
+;; @param A: value to store
+;; @modifies X
+;;********************************************************************************
 .ident(.concat(_RBUF_NAME, "_write")):
 .scope
     ; lda kp_VALUES, x  ; load the char in a
diff --git a/system/io_W65C22.h65 b/system/io_W65C22.h65
index 31d3ba8..3c3eeca 100644
--- a/system/io_W65C22.h65
+++ b/system/io_W65C22.h65
@@ -1,6 +1,6 @@
 ;;********************************************************************************
 ;; @module IO-W65C22
-;; @type utility
+;; @ingroup system
 ;; @device Western Design - W65C22N Versatile Interface Adapter
 ;; @details
 ;;********************************************************************************
@@ -139,7 +139,7 @@ INCLUDE_IOW65C22 = 1
 
 ;;********************************************************************************
 ;; @macro Enable an interrupt source
-;; @modifies: A
+;; @modifies A
 ;; @param flag: A flag of the interrupt flag register (IO::IRQ)
 ;;********************************************************************************
 .macro IO_EnableIRQ ioaddr, flag
@@ -148,7 +148,7 @@ INCLUDE_IOW65C22 = 1
 .endmacro
 ;;********************************************************************************
 ;; @macro Disable an interrupt source
-;; @modifies: A
+;; @modifies A
 ;; @param flag: A flag of the interrupt flag register (IO::IRQ)
 ;;********************************************************************************
 .macro IO_DisableIRQ ioaddr, flag
diff --git a/system/irq_handler.h65 b/system/irq_handler.h65
index 1964091..5a780d4 100644
--- a/system/irq_handler.h65
+++ b/system/irq_handler.h65
@@ -1,6 +1,6 @@
 ;;********************************************************************************
-;; @module irq_handler
-;; @type system
+;; @module WIP irq handler with jump tables and stuff
+;; @ingroup system
 ;;********************************************************************************
 .ifndef INCLUDE_IRQ_HANDLER
 INCLUDE_IRQ_HANDLER = 1
diff --git a/system/keypad.h65 b/system/keypad.h65
index d5582d0..bda0a85 100644
--- a/system/keypad.h65
+++ b/system/keypad.h65
@@ -1,12 +1,12 @@
 ;;********************************************************************************
 ;; @module keypad4x4
-;; @type driver
 ;; @device 4x4 Matrix Keypad
 ;; @details
 ;;   The LCD must be connected to a W65C22N Interface Chip:
 ;;     - IO.RA0-7  -> 
 ;; @requires KP_IO: Base Address of IO Chip
 ;; @depends IO-W65C22N 
+;; @ingroup drivers
 ;;********************************************************************************
 .ifndef INCLUDE_KEYPAD
 INCLUDE_KEYPAD = 1
diff --git a/system/lcd.h65 b/system/lcd.h65
index 3b10363..69f619d 100644
--- a/system/lcd.h65
+++ b/system/lcd.h65
@@ -1,6 +1,6 @@
 ;;********************************************************************************
 ;; @module LCD-W164B
-;; @ingroup driver
+;; @ingroup drivers
 ;; @device ELECTRONIC ASSEMBLY - W164B-NLW
 ;; @details
 ;;   The LCD must be connected to a W65C22N Interface Chip:
@@ -18,7 +18,7 @@ INCLUDE_LCD = 1
 
 ;;********************************************************************************
 ;; @brief LCD character display
-;; @ingroup driver
+;; @ingroup drivers
 ;;********************************************************************************
 .scope lcd
 LCD_IO = IO1
diff --git a/system/lcd.s65 b/system/lcd.s65
index a419c28..7ed8ec6 100644
--- a/system/lcd.s65
+++ b/system/lcd.s65
@@ -45,7 +45,7 @@ _charcount:  .res 1
 ;;********************************************************************************
 ;; @function Set the cursor to a position
 ;; @param A: cursor position: `(lcd::LINEX + offset)`, where offset € [$0, $f]
-;; @details:
+;; @details
 ;;  If the position is too large, it will be set to char 4 in line 2
 ;; @returns A: the cursor position
 ;;********************************************************************************
@@ -109,7 +109,7 @@ _charcount:  .res 1
 ;;********************************************************************************
 ;; @function Print a null-terminated string
 ;; @param ARG0-1 Address of the string to print
-;; @modifies: A,Y
+;; @modifies A,Y
 ;; @returns Y: Length of the string
 ;;********************************************************************************
 .proc print
@@ -143,7 +143,7 @@ _charcount:  .res 1
 ;; @param A: The ASCII code: 0-7
 ;; @param ARG0-1: Start address of the 8 bytes describing the character
 ;; @returns: C: 0 => success, 1 => invalid argument
-;; @modifies: A,Y
+;; @modifies A,Y
 ;;********************************************************************************
 .proc set_custom_char
     cmp #8
diff --git a/system/ps2_keyboard.h65 b/system/ps2_keyboard.h65
index 7e365d5..174d272 100644
--- a/system/ps2_keyboard.h65
+++ b/system/ps2_keyboard.h65
@@ -1,7 +1,7 @@
 ;;********************************************************************************
 ;; @module ps2_keyboard 
 ;; @ingroup drivers
-;; @details:
+;; @details
 ;;  Support for a PS2 Keyboard using the shift register of a 6522 VIA
 ;;  @section reading Reading a scancode/command answer
 ;;   Pressing a key causes 11 bits to be sent: 1 start - 8 scancode - 1 parity - 1 stop 
@@ -49,7 +49,7 @@ VIA = IO1
 ;;  Calculate the appropriate value using: @f$ N_\text{cycles} = 230 \times f_\text{in MHZ} @f$
 ;;  - 230 \@ 1MHz
 ;;  - 400 \@ 1.84 MHz
-;; @clock_dependant
+;; @clock_dependent
 TIMER_RECV = 400
 ;; @brief #clock cycles to wait after loading the SR a second time while sending a command to the keyboard
 ;; @details
@@ -61,7 +61,7 @@ TIMER_RECV = 400
 ;;  Values that seem to work:
 ;;  - 230 \@ 1MHz
 ;;  - 400 \@ 1.84 MHz
-;; @clock_dependant
+;; @clock_dependent
 TIMER_SEND = 400
 
 PULL_REG = IO::RANH
diff --git a/system/ps2_keyboard.s65 b/system/ps2_keyboard.s65
index 841c197..b2fb5c5 100644
--- a/system/ps2_keyboard.s65
+++ b/system/ps2_keyboard.s65
@@ -25,7 +25,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 ; these are macros and not subroutines to save time during the interrupt handler (no jsr, rts)
 ;;********************************************************************************
 ;; @macro Enable the clock signal from the keyboard
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  Stop pulling the keyboards clock low
 ;;********************************************************************************
@@ -38,7 +38,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @macro Disable the clock signal from the keyboard
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  Pulls the keyboards clock low
 ;;********************************************************************************
@@ -56,7 +56,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @macro Stop pulling the keyboard data pin low
-;; @modifies: A
+;; @modifies A
 ;;********************************************************************************
 .macro _StopPullDataLow
     ; set pin to input
@@ -67,7 +67,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @macro Pull the keyboard data pin low
-;; @modifies: A
+;; @modifies A
 ;;********************************************************************************
 .macro _PullDataLow
     ; set pin to output
@@ -88,7 +88,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 ;;  - Initialize variables to 0
 ;;  - Clear the VIAs shift register and set T2 to oneshote mode
 ;;  - Set scancode_handler to immediately return (dont handle scancodes)
-;; @modifies: A
+;; @modifies A
 ;;********************************************************************************
 .proc init
     _DisableClock
@@ -113,7 +113,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 ;; @details
 ;;  - use the shift register interrupts to read the first 8 bits
 ;;  - configure timer for timing the read of the last 3 bits
-;; @modifies: A
+;; @modifies A
 ;;********************************************************************************
 .proc begin_receive
     ; disable timer interrupts (this might be called while waiting on the last 3 bits)
@@ -154,7 +154,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @function Read the first 8 bits an
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  - read shift register
 ;;  - disable shift register interrupts
@@ -181,7 +181,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @function Read the last 3 bits after after timer 2 is up
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  - read shift register
 ;;  - disable timer 2 interrupts
@@ -260,7 +260,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 ;;
 ;;   If ANY of the bytes in cmd_response is 0xFE, the command failed.
 ;;  
-;; @modifies: A,X,Y
+;; @modifies A,X,Y
 ;; @param A: The command byte
 ;; @param X: The data byte or NO_DATA if only the command byte should be sent
 ;; @param Y: The number of data bytes expected to receive. Must be one of {0, 1, 2}
@@ -284,7 +284,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @function Send a byte to the keyboard
-;; @modifies: A,X,Y
+;; @modifies A,X,Y
 ;; @param A: The byte to send
 ;; @details
 ;;  - pull clock low to stop keyboard transmissions
@@ -343,7 +343,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @function Send the lasts 3 bits 
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  - load the remaining 3 bits of the transmission into the shift register
 ;;  - disable shift register interrupts
@@ -365,7 +365,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 
 ;;********************************************************************************
 ;; @function Setup VIA to receive the keyboard's answer
-;; @modifies: A
+;; @modifies A
 ;; @details
 ;;  - disable timer 2 interrupts
 ;;  - pull clock low
@@ -416,7 +416,7 @@ scancode_handler:       .res 2  ;; pointer to a function that handles new scanco
 ;;
 ;;   If ANY of the bytes in cmd_response is 0xFE, the command failed.
 ;;  
-;; @modifies: A,X,Y
+;; @modifies A,X,Y
 ;; @param A: The command byte
 ;; @param X: The data byte or NO_DATA if only the command byte should be sent
 ;; @param Y: The number of data bytes expected to receive. Must be one of {0, 1, 2}
diff --git a/system/spi.h65 b/system/spi.h65
index 9687e16..4281203 100644
--- a/system/spi.h65
+++ b/system/spi.h65
@@ -14,7 +14,7 @@ INCLUDE_SPI = 1
 ;; @details
 ;;  This requires the data line to be hooked up to `CB2` and the clock to `CB1`.
 ;;  The VIA will be set to shift in the data into the shift register under the external clock.
-;; @ingroup driver
+;; @ingroup drivers
 ;; @see via_hardware_bug "VIA external clock bug"
 ;;********************************************************************************
 .scope spi_p
diff --git a/system/system.h65 b/system/system.h65
index 098989d..d51ae35 100644
--- a/system/system.h65
+++ b/system/system.h65
@@ -1,21 +1,25 @@
-;********************************************************************************
-; @module system
-; @type header
-; @details
-;   Variable definitions for the current hardware setup
-;********************************************************************************
+;;********************************************************************************
+;; @module system
+;; @ingroup system
+;; @details
+;;   Variable definitions for the current hardware setup
+;;********************************************************************************
 
 .ifndef INCLUDE_SYSTEM
 INCLUDE_SYSTEM = 1
-; reserved RAM addresses
-; 00-0f - free use  (Z0-Z15)
-; 10-1f - arguments / return values (ARG0-ARG15)
-; 20-ff - free
-; 0100 - 01FF Stack
-; 0200,0201 keybuffer write/read pointer
-; 0202-02ff keybuffer
-; 0300 lcd character counter
 
+;;********************************************************************************
+;; @page system_stuff More System stuff
+;; @subsubsection ram_reserved Reserved RAM addresses
+;;   - 00-0f - free use  (Z0-Z15)
+;;   - 10-1f - arguments / return values (ARG0-ARG15)
+;;   - 20-ff - free
+;;   - 0100 - 01FF Stack
+;;   - 0200,0201 keypad keybuffer write/read pointer
+;;   - 0202-02ff keypad keybuffer
+;;   - 0300 lcd character counter
+;; @ingroup system
+;;********************************************************************************
 
 .include "io_W65C22.h65"
 .include "utility.h65"
diff --git a/util/parity.h65 b/util/parity.h65
index 3b78ad3..f0d63f2 100644
--- a/util/parity.h65
+++ b/util/parity.h65
@@ -5,7 +5,7 @@ INCLUDE_PARITY = 1
 
 ;;********************************************************************************
 ;; @macro Calculate even parity
-;; @modifies: A, X, Y
+;; @modifies A, X, Y
 ;; @returns A: 0 - even number of set bits, 1 - uneven number of set bits
 ;; @returns Y: The number of set bits in the byte
 ;;********************************************************************************
@@ -21,7 +21,7 @@ INCLUDE_PARITY = 1
 ;; @details
 ;;  Count the number of set bits in Y.
 ;;  
-;; @modifies: A, X, Y
+;; @modifies A, X, Y
 ;; @returns A: 1 - even number of set bits, 0 - uneven number of set bits
 ;; @returns Y: The number of set bits in the byte
 ;;********************************************************************************
diff --git a/util/parity.s65 b/util/parity.s65
index a340bbb..f0385ac 100644
--- a/util/parity.s65
+++ b/util/parity.s65
@@ -4,7 +4,7 @@
 ;; @details
 ;;  Count the number of set bits in Y.
 ;;  
-;; @modifies: A, X, Y
+;; @modifies A, X, Y
 ;; @returns Y: The number of set bits in the byte
 ;;********************************************************************************
 .proc count_set_bits
diff --git a/util/string.h65 b/util/string.h65
index b14bba0..2e47a5e 100644
--- a/util/string.h65
+++ b/util/string.h65
@@ -46,7 +46,7 @@ Import str, uint8_to_hex_str, uint_to_hex_str
 ;; @param out:   Output string address
 ;; @param x0-x9: Additional parameters
 ;; @warning Addresses as additional paramters must be passed like this `#<addr,#>addr`
-;; @modifies: A, X, Y, ARG4, ARG5
+;; @modifies A, X, Y, ARG4, ARG5
 ;; @see str::strf
 ;;********************************************************************************
 .macro Strf fmt,out,x0,x1,x2,x3,x4,x5,x6,x7,x8,x9
diff --git a/util/string.s65 b/util/string.s65
index b427311..5781d16 100644
--- a/util/string.s65
+++ b/util/string.s65
@@ -31,7 +31,7 @@ digits:  .res 1
 ;; @param ARG2-3: Output string address
 ;; @param ARG4+:  Additional parameters
 ;; @returns 
-;; @modifies: A, X, Y, ARG4, ARG5
+;; @modifies A, X, Y, ARG4, ARG5
 ;;********************************************************************************
 .proc strf
     stz out_idx