Clean up hardware section

hardware/raspberrypi/README.md

@@ -2,17 +2,17 @@
 
 The hardware in the Raspberry Pi
 
-- [Schematics](schematics.md)
+- [Schematics](schematics/README.md)
     - Schematics for the Raspberry Pi Model A, B and B+
-- [BCM2835](bcm2835.md)
+- [BCM2835](bcm2835/README.md)
     - The Broadcom processor used in Raspberry Pi Model A, B and B+
-- [Mechanical Drawing](Raspberry-Pi-B-Plus-V1.2-Mechanical-Drawing.pdf)
-    - A mechanical drawing of the Raspberry Pi Model B+
-- [GPIO](gpio.md)
-    - General Purpose Input/Output pins on the Raspberry Pi
-- [Power](power.md)
+- [Mechanical Drawings](mechanical/README.md)
+    - Mechanical drawings of the Raspberry Pi Model B+
+- [Power](power/README.md)
     - Powering the Raspberry Pi
-- [USB](usb.md)
+- [USB](usb/README.md)
     - USB on the Raspberry Pi
-- [SPI](spi.md)
+- [GPIO](gpio/README.md)
+    - General Purpose Input/Output pins on the Raspberry Pi
+- [SPI](spi/README.md)
     - SPI on the Raspberry Pi

hardware/raspberrypi/bcm2835.md → hardware/raspberrypi/bcm2835/README.md

@@ -1,6 +1,6 @@
 # BCM2835
 
-The Broadcom chip used in the Raspberry Pi Model A and Model B
+The Broadcom chip used in the Raspberry Pi Model A, B and B+
 
 Please refer to:
 

hardware/raspberrypi/gpio.md → hardware/raspberrypi/gpio/README.md

@@ -4,11 +4,11 @@ General Purpose Input/Output pins on the Raspberry Pi
 
 ## Overview
 
-This page expands on the technical features of the GPIO pins available on BCM2835 in general. For usage examples, see the [GPIO Usage](../../usage/gpio/README.md) section. When reading this page, reference should be made to the BCM2835 ARM Peripherals [Datasheet](bcm2835.md), section 6.
+This page expands on the technical features of the GPIO pins available on BCM2835 in general. For usage examples, see the [GPIO Usage](../../../usage/gpio/README.md) section. When reading this page, reference should be made to the BCM2835 ARM Peripherals [Datasheet](../bcm2835/README.md), section 6.
 
 GPIO pins can be configured as either general-purpose input, general-purpose output or as one of up to 5 special alternate settings, the functions of which are pin-dependant.
 
-There are 3 GPIO banks on BCM2835. 
+There are 3 GPIO banks on BCM2835.
 
 Each of the 3 banks has its own VDD input pin. On Raspberry Pi, all GPIO banks are supplied from 3.3V. **Connection of a GPIO to a voltage higher than 3.3V will likely destroy the GPIO block within the SoC.**
 
@@ -20,9 +20,9 @@ The GPIO connections on the BCM2835 package are sometimes referred to in the per
 
 The pads are configurable CMOS push-pull output drivers/input buffers. Register-based control settings are available for
 
-* Internal pull-up / pull-down enable/disable
-* Output [drive strength](http://www.scribd.com/doc/101830961/GPIO-Pads-Control2)
-* Input Schmitt-trigger filtering
+- Internal pull-up / pull-down enable/disable
+- Output [drive strength](http://www.scribd.com/doc/101830961/GPIO-Pads-Control2)
+- Input Schmitt-trigger filtering
 
 ### Power-On States
 
@@ -32,18 +32,16 @@ All GPIOs revert to general-purpose inputs on power-on reset. The default pull s
 
 Each GPIO pin, when configured as a general-purpose input, can be configured as an interrupt source to the ARM. Several interrupt generation sources are configurable:
 
-* Level-sensitive (high/low)
-* Rising/falling edge
-* Asynchronous rising/falling edge
+- Level-sensitive (high/low)
+- Rising/falling edge
+- Asynchronous rising/falling edge
 
 Level interrupts maintain the interrupt status until the level has been cleared by system software (e.g. by servicing the attached peripheral generating the interrupt).
 
 The normal rising/falling edge detection has a small amount of synchronisation built into the detection. At the system clock frequency, the pin is sampled with the criteria for generation of an interrupt being a stable transition within a 3-cycle window, i.e. a record of "1 0 0" or "0 1 1". Asynchronous detection bypasses this synchronisation to enable the detection of very narrow events.
 
-
 ## Alternative Functions
 
 Almost all of the GPIO pins have alternative functions. Peripheral blocks internal to BCM2835 can be selected to appear on one or more of a set of GPIO pins, for example the I2C busses can be configured to at least 3 separate locations. Pad control, such as drive strength or Schmitt filtering, still applies when the pin is configured as an alternate function.
 
-
-[Please refer to the eLinux.org page](http://elinux.org/RPi_Low-level_peripherals)
+For more detailed information see the [Low level peripherals](http://elinux.org/RPi_Low-level_peripherals) page on the elinux wiki

hardware/raspberrypi/mechanical/README.md

@@ -0,0 +1,6 @@
+# Mechanical Drawings
+
+Mechanical drawings of the Raspberry Pi Model B+
+
+- [PDF](Raspberry-Pi-B-Plus-V1.2-Mechanical-Drawing.pdf)
+- [DXF](Raspberry-Pi-B-Plus-V1.2-Mechanical-Drawing.dxf)