Paul,
Do you have to use a relay ?
Would solid state H bridge work for you ?
What are your constraints ?   Price ? Protection against voltage  
spikes ?   ???

When I googled , the motor appears to be rated for 12V , 60ma.
> The motor has a stall current of only 450mA.

An H-bridge would work with this motor.
Here is an example:   http://www.sparkfun.com/commerce/product_info.php?products_id=315
Other people on this list can probably give better suggestions for an  
H-Bridge.
You should be able to use one pin to control on-off and direction  
using high, low and tri-state.
Or use two pins to control direction and on-off.

Answer the questions above and we can help you some more.

Gus

> On Dec 29, 2009, at 2:26 AM, ivp wrote:
>
>> I want to switch on/off and change the rotation direction of the
>> electric motor PC-130SF-09400T-NR
>
> http://www.nichibo-motor.com/proType_e.php?proType=5
>
>> So the PIC16F877A should control two electric motors with two
>> relay this way.
>
> Paul, to do that with relays you'd need two per motor. One to control
> the power supply (ie on/off) and one to change direction
>
> Like this
>
> http://home.clear.net.nz/pages/joecolquitt/varprop4.gif
>
> However, you could replace the power relay with a FET / transistor
> between the direction relay and ground. See attached. Turning this
> off will break the circuit
>
> The motor has a stall current of only 450mA. Something like a BC639,
> and some variants of the BC337 are 800mA. There are several small
> FETs that will do 1A<motor_control.gif>--
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