Question about 2 bit counter example.

Hi,

I am new to electronics and VHDL etc.

I am trying to understand the first 2 bit counter example. In this PDF:

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I think the clock signal goes as follows: high, low, high, low, high, low.

So that's just the same as:

101010101010101010101

The clock signal is connected to a T_flipflop and goes out port Q0 (and also ff0 I dont understand what that is... just some internal state thing ? but ok)

So after the clock signal passess through the T_flipflop the new signal will look like: old clock signal:

1010101010101010101010

( t_flipflop is explained at

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)

new Q0 signal:

1100110011001100110011

Now the new Q0 signal also goes to another invertor...

So after the invertor the interver signal will look like:

( I think an invertor just inverts it right ? ;) )

Q0 inverter signal:

0011001100110011001100

Now the Q0 inverter signal enters another t_flipflop and it's output is Q1. (also ff1)

Q1 signal:

001000100010001000100

So now we have three signals:

The original clock signal:

101010101010101010101010

The Q0 flipflop signal:

110011001100110011001100

The Q1 flipflop signal:

001000100010001000100010

Ok I find this a little bit weird.

For a counter I would expect the output to be the following: Q0 Q1:

00 01 10 11 00 01 10 11

However the output seems to be:

10 10 01 00 10 10 01 00 10 10 01 00 10 10 01 00 10 10 01 00 10 10 01 00

This is totally different than how I would expect it too work...

Have I made a mistake in my reasoning somewhere ?

Is there a part I dont understand ? maybe the invertor works differently ?

Or is the PDF/manual a weird/bogus/wrong example of a 2 bit counter ???

Bye, Skybuck.

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Skybuck Flying
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