Pull up - pull down
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I hate being so dumb at this, oh well... :-)
The Motor Mind B module has a BRAKE pin which is active low, meaning
grounding this pin will stop the motor. From Vcc, I have a 10K
resistor to this pin, which sets it high, allowing the motor to run.
To control the BRAKE, I thought I could connect the BRAKE pin to a
BS2 pin, then set the pin to either Output High (motor runs) or Input
(pin sinks current, grounding BRAKE, and motor stops)
What I found was this:
BS2 pin Output High = motor runs
BS2 pin Output Low = motor brakes
Or, I could connect BS2 pin to BRAKE directly, and get the same
results, eliminating the Vcc and resistance. But even a 1K
resistance between the BS2 pin and BRAKE has no effect, the motor
runs.
Am I missing something here? Does a direct connection pose a damage
risk to either the BS2 or the motor minder? Or should I go with the
Vcc/Pull Up scheme?
Thanks guys!
Kurt
The Motor Mind B module has a BRAKE pin which is active low, meaning
grounding this pin will stop the motor. From Vcc, I have a 10K
resistor to this pin, which sets it high, allowing the motor to run.
To control the BRAKE, I thought I could connect the BRAKE pin to a
BS2 pin, then set the pin to either Output High (motor runs) or Input
(pin sinks current, grounding BRAKE, and motor stops)
What I found was this:
BS2 pin Output High = motor runs
BS2 pin Output Low = motor brakes
Or, I could connect BS2 pin to BRAKE directly, and get the same
results, eliminating the Vcc and resistance. But even a 1K
resistance between the BS2 pin and BRAKE has no effect, the motor
runs.
Am I missing something here? Does a direct connection pose a damage
risk to either the BS2 or the motor minder? Or should I go with the
Vcc/Pull Up scheme?
Thanks guys!
Kurt
Comments
Your correct about how to control the brake, but when you set a pin to
input mode, it can't sink any current.
I would leave the control pulled to Vcc through your 10k resistor, when you
want the motor to run, configure the pin as an input, bring pin low to
activate break
fwiw
steve
At 09:19 PM 02/01/2001 -0000, you wrote:
>I hate being so dumb at this, oh well... :-)
>
>The Motor Mind B module has a BRAKE pin which is active low, meaning
>grounding this pin will stop the motor. From Vcc, I have a 10K
>resistor to this pin, which sets it high, allowing the motor to run.
>To control the BRAKE, I thought I could connect the BRAKE pin to a
>BS2 pin, then set the pin to either Output High (motor runs) or Input
>(pin sinks current, grounding BRAKE, and motor stops)
>
>What I found was this:
>BS2 pin Output High = motor runs
>BS2 pin Output Low = motor brakes
>
>Or, I could connect BS2 pin to BRAKE directly, and get the same
>results, eliminating the Vcc and resistance. But even a 1K
>resistance between the BS2 pin and BRAKE has no effect, the motor
>runs.
>
>Am I missing something here? Does a direct connection pose a damage
>risk to either the BS2 or the motor minder? Or should I go with the
>Vcc/Pull Up scheme?
>
>Thanks guys!
>
>Kurt
>
>
>
>
>