Add tech items and botany

index.wiki

@@ -13,16 +13,18 @@ _Ideas.md and Classes.md are encrypted, so these links will not work_
 * [[Classes.md.gpg]] - My class info for Graduation
 * [[splash]] - The splash page
 
-== Tech notes ==
+== [[tech/index|Tech notes]] ==
 
 * [[tech/security|Security]] - Security tools and techniques
 * [[tech/development|Development]] - Development tools
 * [[tech/algorithms|Algorithms & Datastructures]] - Algorithms and Data structures
 * [[tech/databases|Databases & SQL]] - Databases and SQL
 * [[tech/os|Operating Systems Design]] - Basic building blocks of an OS
+* [[tech/embedded|Embedded Programming]] - Embedded Systems like arduinos and (kinda) pi's
+* [[electronics|Digital and Analog]] - Digital and analog electronics
 * [[tech/misc|Misc]] - Miscellaneous tools
 
-== Languages ==
+== [[lang/index|Languages]] ==
 
 * [[lang/C|C]] 
 * [[lang/C++|C++]]
@@ -36,7 +38,22 @@ _Ideas.md and Classes.md are encrypted, so these links will not work_
 * [[lang/Go|Go]]
 * [[lang/sql|SQL]]
 
-== School ==
+== [[sci/index|Science]] ==
+
+* [[sci/chemistry|Chemistry]]
+* [[sci/physics|Physics]]
+
+== [[botany/index|Botany]] ==
+
+* [[botany/vegies|Vegies]]
+* [[botany/hydroponics|Hydroponics]]
+* [[botany/aquaponics|Aquaponics]]
+
+
+
+== Local to GentooBox ==
+
+=== School ===
 _Use gf keybinding to open the link in vim_
 - Digital Design
   - ~/school/Advanced\ Digital\ Design
@@ -51,7 +68,7 @@ _Use gf keybinding to open the link in vim_
 - Human Biology
   - ~/school/Human\ Biology
 
-== Projects ==
+=== Projects ===
 _Use gf keybinding to open the link in vim_
 - Dashboard
   - ~/code/dashboard

tech/RISC.wiki

@@ -0,0 +1,6 @@
+= RISC =
+
+Reduced Instruction Set Computer. Most have [[pipelining]],
+[[simple_addressing|Simple Addressing]], and low clock rates
+
+[[index]]

tech/algorithms.wiki

@@ -31,4 +31,13 @@ Different ways to store and operate on data, with differing efficiency
 * [[bucket|Bucket]]
 * [[counting|Counting]]
 
-[[../index]]
+== Paradigms ==
+
+* [[simple_recurison|Simple Recursion]]
+* [[divide_and_conquer|Divide and Conquer]]
+* [[dynamic_programming|Dynamic Programming]]
+* [[greedy_algorithm|Greedy Algorithms]]
+* [[brute_force|Brute Force]]
+* [[randomized_algorithm|Randomized Algorithms]]
+
+[[index]]

tech/arduino_nano.wiki

@@ -0,0 +1,68 @@
+= Arduino Nano =
+
+A very small arduino product, better for hobby embedding 
+
+see [[arduino_techniques|Programming Techniques]]
+
+== Features ==
+
+* ATMEL AVR ATmega328P microcontroller
+* 8 bit @16Mhz
+* 2Kbytes SRAM 
+* 32Kbytes flash
+* 1Kbytes EEPROM
+* Three on board LED's
+* 20 IO pins
+* 6 PWM and 6 ADC
+
+== Notes ==
+
+=== Memory ===
+
+* AVR instructions are 16 or 32bits wide, therefore the flash is 16K x 16
+* EEPROM has endurance of ~10000 write cycles
+* Program counter is 14 bits wide
+* First 32 memory locations (0x0000 - 0x001F) are registers
+* Next 64 registers are standard IO (0x0020 - 0x005F)
+* Next 160 are extended IO (0x0060 - 0x00FF)
+* Everything else is SRAM (0x0100 - 0x08FF)
+
+=== IO ===
+
+* GPIO pins
+* Have a Data Direction Register (DDR)
+  - Sets if data should go in or out
+* Is kept up via a [[multiplexer]] to decide which bit
+
+=== Pins ===
+
+* PortC
+  - Port C data regiser
+  - 0x28
+  - R/W 8bits
+* DDRC
+  - Port C data direction register
+  - 0x27
+  - R/W 8bits
+* PINC
+  - Port C input pints address
+  - 0x26
+  - R 8bits
+* PortB
+  - Port B data register
+  - 0x25
+  - R/W 8bits
+* DDRB
+  - Port B data direction register
+  - 0x24
+  - R/W 8bits
+* PINB
+  - Port B Input pins address
+  - 0x23
+  - R 8bit
+
+Same pattern:
+* PortD
+  - 0x2B - 0x29
+
+[[embedded]]

tech/arduino_techniques.wiki

@@ -0,0 +1,47 @@
+= Arduino Programming Techniques =
+
+This is mostly gonna be C++
+
+== Accessing a GPIO line ==
+
+{{{
+    //data direction register bit
+    unsigned char *portDDRB;
+    
+    portDDRB = (unsigned char *) 0x24;
+  }}}
+
+First we get an 8bit pointer and load it with a hard coded value of 
+the data-space address for that register
+
+See [[arduino_nano#Pins]]
+
+== Bit masks ==
+
+{{{
+    #define BIT6_MASK 0x40 // 0100 0000
+    #define BIT5_MASK 0x20 // 0010 0000
+    
+    *register_pointer = (*regiser_pointer) & (~BIT6_MASK);
+    *register_pointer = (*regiser_pointer) | BIT5_MASK;
+
+  }}}
+  
+For the first one we find the compilemnt then '&' it with the current 
+register values, which will only flip the selected bit.
+
+For the second one we '|' it with the contents, setting a 1 in the 5th position
+
+== Polling GPIO pins ==
+
+repeatedly reading the value of the input pins and comparing the current value
+to the previously-read value to determine if an external signal event has
+occurred. 
+
+We can do this by comparing the last known value of the gpio pin with the
+current one
+
+See [[arduino_nano#Pins]]
+
+
+[[embedded]]

tech/buffer.wiki

@@ -0,0 +1,6 @@
+= Buffer =
+
+A Buffer is a flip flop that holds the current value, and can be read when a
+signal is given to it. Has an input, output, and swith to read from it.
+
+[[electronics]]

tech/databases.wiki

@@ -10,3 +10,5 @@ network, with caching and other optimizations.
 == SQL ==
 
 See [[../lang/sql]]
+
+[[index]]

tech/development.wiki

@@ -18,4 +18,4 @@
 
 
 
-[[../index|Index]]
+[[index]]

tech/electronics.wiki

@@ -0,0 +1,15 @@
+= Electronics =
+
+Both digital and analog components
+
+
+= Combinational =
+
+* [[multiplexer|Multiplexer]]
+
+
+= Sequential =
+
+* [[buffer|Buffer]]
+
+[[index]]

tech/embedded.wiki

@@ -0,0 +1,24 @@
+= Embedded Systems =
+
+Systems that are in other things, and therefore the computer is hidden from the
+user, sometimes so that they don't even know there is a computer
+
+== Arduino ==
+
+* https://www.microchip.com/en-us/product/ATmega328
+* [[RISC]] Processor type
+
+=== Line of products ===
+
+* [[arduino_nano|Arduino Nano]]
+* [[arduino_uno|Arduino Uno]]
+
+
+=== Programming ===
+
+* [[../lang/C|C]]
+* [[../lang/C++|C++]]
+* [[arduino_techniques|Techniques]]
+
+
+[[index]]

tech/hash_table.wiki

@@ -0,0 +1,25 @@
+= Hash table =
+
+The almighty O(1) accessing data structure. Uses a hash function so really its
+only as fast as your hash function. Comes in associate and non-associate
+flavors.
+
+== Good For ==
+
+* Crazy fast [[look]] ups
+
+== Bad for ==
+
+* Non basic data types (unless you create a really good hash function)
+
+== Optimize ==
+
+One of the ways I like to use these is to hold pointers. That's basically the
+idea behind a LRUCache and other types of data-structure caches. They are also
+usually an array of linked list buckets. If you can get a perfect hash function
+(gperf) then its a wonderful choice, as it will never collide and always only
+take O(1) time. Also if you're willing to test a set of common sets of data, you
+can choose to not have a linked list set of buckets, however depending on how
+you deal with collisions it can get very bad very fast.
+
+[[algorithms]]

tech/index.wiki

@@ -0,0 +1,15 @@
+= Tech =
+
+Everything dealing with my awful addiction to computers
+
+== Major sections ==
+* [[security|Security]] - Security tools and techniques
+* [[development|Development]] - Development tools
+* [[algorithms|Algorithms & Datastructures]] - Algorithms and Data structures
+* [[databases|Databases & SQL]] - Databases and SQL
+* [[os|Operating Systems Design]] - Basic building blocks of an OS
+* [[embedded|Embedded Programming]] - Embedded Systems like arduinos and (kinda) pi's
+* [[electronics|Digital and Analog]] - Digital and analog electronics
+* [[misc|Misc]] - Miscellaneous tools
+
+[[../index]]

tech/misc.wiki

@@ -2,4 +2,4 @@
 
 Misc. Stuff relating to computers and tech in general
 
-[[../index]]
+[[index]]

tech/multiplexer.wiki

@@ -0,0 +1,32 @@
+= Multiplexer =
+
+Combines several signals into one
+
+Consists of 
+* An output
+* _n_ inputs, 
+* log,,2,,(_n_) selectors
+
+This alone allows us using the selectors, to choose which input
+
+This is best shown with a 2 input multiplexer, which only needs 1 selector
+
+{{{
+in0 |---|
+----|   |Out
+in1 |   |---
+----|   |
+    |---|
+      |
+ sel  |
+}}}
+
+| sel | output |
+|-----|--------|
+| 0   | in0    |
+| 1   | in1    |
+
+And thats all there is to it. This scales up with several inputs, 
+several selectors, and one output
+
+[[electronics]]

tech/nmap.wiki

@@ -1,5 +1,3 @@
-[[index]]
-
 = nmap =
 
 A great tool for scanning hosts over the network
@@ -45,3 +43,4 @@ A great tool for scanning hosts over the network
  - Usage: -p<1-65535>
  - Scans specified ports only. use -p- to scan every port
 
+[[index]]

tech/os.wiki

@@ -3,4 +3,8 @@
 The primary 'program' running on a machine that allows a user to run several
 programs at once, manages drivers and hardware abstraction, etc
 
-[[../index]]
+== CPUs ==
+
+* [[RISC]]
+
+[[index]]

tech/queue.wiki

@@ -12,5 +12,10 @@ from the back
 
 * Everything else
 
+== Optimize ==
+
+Only implement this as a linked list, as all insert and removal (which is the
+only operation queues have really), will be in O(1) time. Really fast, just no
+cache optimizations, but its _usually_ a valid trade-off
 
 [[algorithms]]

tech/security.wiki

@@ -4,7 +4,7 @@ Tools useful for security, either offensive or defensive
 
 == Reconnaissance ==
 
-* [[recon/nmap|nmap]] - port scanner
+* [[nmap|nmap]] - port scanner
 
 
 
@@ -13,4 +13,4 @@ Tools useful for security, either offensive or defensive
 
 
 
-[[../index.wiki]]
+[[index.wiki]]

tech/skip_list.wiki

@@ -0,0 +1,21 @@
+= Skip List =
+
+A more specialized version of a list with log(n) search, insertion, and
+deletion (on average).
+
+== Good For ==
+
+* Keeping an order with fast lookups and removals
+
+== Bad For ==
+
+* Space constrained enviroments (nlogn space usage)
+
+
+== Notes ==
+
+Honestly things like a B-Tree are better alternatives, but sometimes you need a
+list like this. 
+
+
+[[algorithms]]

tech/stack.wiki

@@ -8,9 +8,15 @@ like
 
 * Keeping an order of things added
 
-
 == Bad For ==
 
 * Everything else
 
+== Optomize ==
+
+You can make this either just an array with a pointer to the top of the stack,
+or as a big single linked list that keeps track of the head. Use the array when
+you know the max number of elements, otherwise use a linked list. If caching is
+a concern, use the array version.
+
 [[algorithms]]