Aim APE1553-1-DS, Руководство по оборудованию

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8
APE1553-1/2(-DS) Hardware Manual
2.3.2.3 GPIO connection
The APE1553 provides eight General Purpose Discrete I/O's (GPIO’s).
Five General Purpose I/O's (GPIO1 - GPIO5) are provided at the HD-DSUB26
frontpanel connector with Avionic Level inputs and outputs.
All eight GPIO's are provided on the B2B-Connector.
The GPIO’s can be used as simple discrete inputs or outputs, for example to generate
strobes (i.e. to another APE1553 board) or to sample a digital input signal generated
externally.
Discrete input signals are always enabled whereas the discrete output must be enabled
by the user. An open collector circuitry is used for the discrete output with 4V provided
by default. An external voltage from 0 to 35V can be supplied externally for switching
higher voltages. Be aware that a series resistor must be provided when a user specific
voltage is connected to a Discrete I/O (Figure 3.8-1). This serial resistor must limit the
current through the open collector transistor to max. 50 mA. Otherwise the open
collector transistor can be damaged. EMC aspects are covered by filter circuitry.
All eight GPIO’s are available on the ribbon cable B2B connector on the mainboard.
The GPIO’s can be used as simple discrete inputs or outputs, for example to generate
strobes (i.e. to another APE1553 board) or to sample a digital input signal generated
externally.
If all the GPIO’s should be provided externally, an optional Breakout Panel, connected
via the B2B connector can be used.
For more information regarding the Breakout-Panel contact factory.
Note:
The discrete outputs don’t provide a series resistor for over current protection. If using a
discrete input, make sure that the output-mode for that discrete is disabled, before
connecting an external voltage, otherwise the transistor can be damaged caused by a
high short circuit current to GND.