PKP
VS1000 P
ROGRAMMER
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UIDE
VSMPG
This operation enables free selection of polarity for outputs, e.g. after reset a pull-up
keeps a control line high, the data register bit is set to 1 and after this the DDR bit is set
to 1 enabling the output.
When a data register bit is set to 0, it is easy to use the I/O pin as open-drain-style
output by changing the direction: as input the line state is 1 by a pull-up, as output the
line is pulled low by the driver.
Possible delays must be documented.
14.2.3
Input Data GPIOx_IDATA
The actual logical levels of the I/O pins are seen in the input data register. Possible
delays must be documented.
14.2.4
Falling Edge Interrupt Enable GPIOx_INT_FALL
If a bit the falling edge interrupt enable register (INT_FALL) is set to 1, a falling edge in
the corresponding pin (even when configured as output) will set the corresponding bit in
the interrupt pending source register (INT_PEND).
14.2.5
Rising Edge Interrupt Enable GPIOx_INT_RISE
If a bit the rising edge interrupt enable register (INT_RISE) is set to 1, a rising edge in
the corresponding pin (even when configured as output) will set the corresponding bit in
the interrupt pending source register (INT_PEND).
14.2.6
Interrupt Pending Source GPIOx_INT_PEND
If any of the bits in the interrupt pending source register (INT_PEND) are set, an interrupt
request is generated. Bits in INT_PEND can be cleared by writing a 1-bit to the bit that
is to be cleared.
Note: the interrupt request will remain asserted until all INT_PEND bits are cleared.
14.2.7
Data Set Mask GPIOx_SET_MASK
A bit mask is written to the data set mask register. All bits that are set in the mask also
set the corresponding bit in the data output register. Other bits retain their old values.
I.e. a logical-OR operation is performed between the data output register old value and
the mask and the result is written to the data output register.
Rev. 0.20
2011-10-04
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