Point Grey Flea3 FL3-U3 - Pulse Width Modulation (PWM); GPIO_CTRL_PIN: 1110 H-1140 H

Point Grey Flea3 USB 3.0 Technical Reference 4 Input/Output Control
4.4 Pulse Width Modulation (PWM)
When a GPIO pin is set to PWM (GPIO Mode 4), the pin will output a specified number of pulses with programmable
high and low duration.
The pulse is independent of integration or external trigger. There is only one real PWM signal source (i.e. two or more
pins cannot simultaneously output different PWMs), but the pulse can appear on any of the GPIO pins.
The units of time are generally standardized to be in ticks of a 1.024 MHz clock. A separate GPIO pin may be
designated as an “enable pin”; the PWM pulses continue only as long as the enable pin is held in a certain state (high
or low).
The pin configured to output a PWM signal (PWM pin) remains in the same
state at the time the ‘enable pin’ is disabled. For example, if the PWM is in a
high signal state when the ‘enable pin’ is disabled, the PWM pin remains in a
high state. To re-set the pin signal, you must re-configure the PWM pin from
GPIO Mode 4 to GPIO Mode 1.
4.4.1 GPIO_CTRL_PIN: 1110h-1140h
These registers provide control over the GPIOpins.
Pin Register
0 GPIO_CTRL_PIN_0 1110h
1 GPIO_CTRL_PIN_1 1120h
2 GPIO_CTRL_PIN_2 1130h
3 GPIO_CTRL_PIN_3 1140h
Field Bit Description
Presence_Inq [0]
Presence of this feature
0: Not Available, 1: Available
[1-11] Reserved
Pin_Mode [12-15]
Current GPIO Mode:
0: Input
1: Output
2: Asynchronous Trigger
3: Strobe
4: Pulse width modulation (PWM)
[16-30]
For Modes 0, 1, and 2: Reserved
For Mode 4 (PWM:) see below
Format:
Revised 9/27/2012
Copyright ©2011-2012 Point Grey Research Inc.
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