General electronics knowledge questions...

[omfgcaps]

sorry if these questions aren't very educated..

1. What is vcc and how is it different from +V?

2. Whats the difference between -v and GND, and what are some examples of situations where you would use one or the other?

3. How can you determine which lines are data, which are voltage, and which lines do nothing? is there a special type of multimeter? for instance, someone figured out which lines on the DMG LCD are data, data, vsync and hsync.

4. How are data lines labeled? how does the label relate to functionality or w/e?



please answer any or all of these questions, your help is appreciated

[mako321]

http://en.wikipedia.org/wiki/IC_power_supply_pin" onclick="window.open(this.href);return false;
It's in there.

[tom61]

1) Basically the same
2) Complicated subject. For the purposes of most electronics that'd end up in a portable, consider them to basically mean the same thing.
3)An oscilloscope or multi-channel digital logic probe while the machine is running, or find a datasheet for the chips inside and work from its pinout to use a standard multimeter to check from the pins of the chip to various connector places.
4)Multiple standards exist for this.

[timmeh87]

for #4, the pins are all just labeled with the name of the node, usually taken from a schematic. When talking about (and making) schematics, 'node' means any continuous line on the schematic (or metal conductor in reality). So nodes can each be named anything, If you are solving stuff with circuit equations you might just call them x and y, or v1 and v2. Usually any nodes hooked up to an integrated circuit will take on the name of the pin that they are connected to. All integrated circuits have names for all of their pins, given in the datasheet.

The point is, the labels on the pins in that diagram are specific to the integrated circuits that they are attached to. In the second image, I see a chip select (CS), read (RD) and write (WR) lines, which makes sense because it says its connected to some SRAM, and all SRAM chips have those pins. All the answers are in the datasheet specific to your integrated circuits.

I hope thats not confusing

Also, logic timing diagrams like this, taken from an n64 cart bus, help people understand how the signals relate to each other. This is similar to the output you would get from a logic analyzer.
http://crazynation.org/N64/n64_cart_info.htm" onclick="window.open(this.href);return false;