Minecraft - redstone basics

Still with the Minecraft and trying to nail down the logic in how redstone circuits work, the wiki's great and all, but at times it's a little disjointed for me. As such I present my experimental results simply so I don't forget them.

The main component of redstone circuits is the power source. As of the date of posting these comprise of five different items - Button, Lever, Pressure Plate, Redstone Torch and Detector Rail. All of these will provide power to any item that requires it, but in specific and slightly different manners.


In terms of providing power a button will provide a surge of power then turn off; a pressure plate will provide power only whilst stood upon; a lever will provide power when turned on; a redstone torch will constantly provide power unless the block to which it is attached is powered*; and a detector rail will provide power only when a minecart passes over it.

All sources will provide power to the block to which they are attached except for a redstone torch*. All sources will also provide power to any block designed to use or transmit power that adjoins it either horizontally or vertically, but not diagonally.

The block to which a source is attached will itself act as a source, again except in the case of redstone torches*, and will thus provide power to any adjoining block designed to use or transmit it.

When connected to a source redstone wire will also act as a source, however it will not provide power to any block directly above itself. If two pieces of redstone wire are placed next to each other they will form a direct path. Power will then only be provided along this path to the block at its end and to the blocks below it.

Redstone wire will also form a path when placed within one block horizontally or vertically to another piece provided an air space exists at the point they would connect. Redstone wire can only carry power for 15 blocks before fading necessitating the use of repeaters for any longer distances.

A repeater is a one-way transmitter of power that can only receive power and send power from opposite directions. When powered it will act as a source in the same manner as a redstone wire path providing power only to the block at its end and the block below it. A repeater will not connect to a wire except when at the same height as it.

Repeaters can be set to delay the transmission of power via setting the spacing between the two 'ends' by repeated right clicking of a placed repeater.

* To screw with the logic a redstone torch is only said to be attached when fixed to the side of a block. When 'free-standing'  it provides power to the same six blocks as the other sources despite being 'attached' to the block below it.