architecture: improve prose CPU Architecture entry

Computer_Architecture/CPU/Arithmetic_Logic_Unit.md

@@ -6,15 +6,15 @@ tags: [CPU]
 
 # Arithmetic Logic Unit (ALU)
 
-The ALU is the centerpiece or core of the [CPU](/Computer_Architecture/CPU/CPU_architecture.md) architecture, where the binary calculations occur. It comprises [logic gates](/Electronics_and_Hardware/Digital_circuits/Logic_gates.md) that execute the instructions passed from memory and where the data stored by the registers is acted upon.
+The ALU is the centerpiece or core of the [CPU](/Computer_Architecture/CPU/CPU_architecture.md) architecture, where the binary calculations occur. All the other components on the CPU chip are appendanges to the execution that occurs within the ALU.
 
-It can execute arithmetic and logical operations on binary numbers. This is where you will find operations conducted by [full-adders and half adders](/Electronics_and_Hardware/Digital_circuits/Half_adder_and_full_adder.md) etc.
+The ALU comprises [logic gates](/Electronics_and_Hardware/Digital_circuits/Logic_gates.md) that execute the instructions passed from memory and where the data stored by the registers is acted upon.
 
-This is the heart of the CPU; all the other components on the CPU chip are appendanges to the execution that occures within the ALU. It is also what is meant by the **core** processor that is referred to in hardware specs of computers, for instance _dual-core_, _quad core_ etc.
+It executes arithmetic and logical operations on binary numbers and thus it is where you will find operations conducted by [full-adders and half adders](/Electronics_and_Hardware/Digital_circuits/Half_adder_and_full_adder.md) etc.
 
-Below is a schematic of a series of logical circuits within the CPU core:
+More specifically, the ALU is responsible for the _execute_ phase of the [fetch, decode, execute cycle](/Computer_Architecture/CPU/Fetch_decode_execute.md).
 
-![74181aluschematic.png](/_img/74181aluschematic.png)
+// Notes on
 
 ### Processor cores
 

Computer_Architecture/CPU/CPU_architecture.md

@@ -6,7 +6,7 @@ tags: [CPU, electromagnetism, clock]
 
 # CPU architecture
 
-At the core of a computer sits the Central Processing Unit. This is the assembly of chips that execute all computation. Instructions are passed to the CPU along the data bus part of the system bus from the memory. The [kernel](/Operating_Systems/The_Kernel.md), also residing in memory sequences and schedules the sending of data to the CPU and manages requests from the CPU for data in memory.
+At the core of a computer sits the Central Processing Unit. This is the assembly of chips that execute all computation. Instructions are passed to the CPU along the data bus part of the [system bus](/Computer_Architecture/Bus.md) from the memory. The [kernel](/Operating_Systems/The_Kernel.md), also residing in memory, sequences and schedules the sending of data to the CPU and manages requests from the CPU for data in memory.
 
 The CPU comprises three core components:
 
@@ -38,12 +38,6 @@ There are five main types of register in the CPU:
 
 See [Arithmetic Logic Unit](/Computer_Architecture/CPU/Arithmetic_Logic_Unit.md)
 
-### Processor cores
-
-The vast majority of general purpose computers are multi-core. This means that the CPU contains more than one processing unit. They are best thought of as mini-CPUs within the main CPU since they each have the same overall Von Neumann architecture.
-
-With Intel processors the two main consumer processors are the i5 and i7. The latter has more cores than the former. Consequently it has faster clock speeds and greater concurrency due to increased threads.
-
 ## Control Unit
 
 The CPU's [controller](/Computer_Architecture/Chipset_and_controllers.md). It takes the instructions in binary form from RAM memory (separate from the CPU, but connected) and then signals to the to ALU and memory registers what it is supposed to do to execute the instructions. Think of it as the overseer that gets the ALU and registers to work together to run program instructions.
@@ -52,7 +46,7 @@ The CPU's [controller](/Computer_Architecture/Chipset_and_controllers.md). It ta
 
 Whilst modern CPUs and multithreading make it appear as though the CPU is capable of running multiple processes at once, access to the CPU is in fact sequential. The illusion of simultaneous computation is due to the fact the processor is so fast that we do not detect the sequential changes. For this to happen, the CPU needs to have a means of scheduling and sequencing processes. This is made possible through the system clock, hence when talking about the speed of the CPU we do so with reference to _clock speeds_ and the _clock cycle_.
 
-The clock's circuitry is based on a quartz crystal system like that used in watches. At precisely timed intervals, the clock sends out pulses of electricity that cause bits to move from place to place within [logic gates](/Electronics_and_Hardware/Digital_circuits/Logic_gates.md) or between logic gates and [registers](/Computer_Architecture/CPU/CPU_architecture.md#registers). This is covered in greater detail in the discussion of [clock signals in digital circuits](/Electronics_and_Hardware/Digital_circuits/Clock_signals.md)
+The clock's circuitry is based on a quartz crystal system like that used in watches. At precisely timed intervals, the clock sends out pulses of electricity that cause bits to move from place to place within [logic gates](/Electronics_and_Hardware/Digital_circuits/Logic_gates.md) or between logic gates and [registers](/Computer_Architecture/CPU/CPU_architecture.md#registers). This is covered in greater detail in the discussion of [clock signals in digital circuits](/Electronics_and_Hardware/Digital_circuits/Clock_signals.md).
 
 Simple instructions such as add can often be executed in just one clock cycle, whilst complex operations such as divide will require a number of smaller steps, each using one cycle.
 
@@ -66,7 +60,7 @@ Each "cycle" is the execution of a process that commences once the [kernel](/Ope
 
 ## Electromagnetism: broader scientific context
 
-Hertz was the scientist who detected electromagentic waves and more broadly in science, we use Hertz to measure the frequency of electromatic wave cycles in a signal.
+Hertz was the scientist who detected [electromagentic waves](/Electronics_and_Hardware/Physics_of_electricity/Electromagnetism.md) and more broadly in science, we use Hertz to measure the frequency of electromatic wave cycles in a signal.
 
 ![](/_img/hertz_wave_freq.gif)
 

DevOps/AWS/SAM/SAM_frequent_commands.md

@@ -0,0 +1,21 @@
+---
+categories:
+  - DevOps
+  - Backend
+tags: [AWS]
+---
+
+# SAM frequent commands
+
+### List users
+
+```
+aws configure list
+aws configure list-profiles
+```
+
+### View profile data
+
+```
+vim ./aws/credentials
+```