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LPC810 Question about connect ACMP_O to SCT input

1 reply [Last post]
Joined: 2013-06-26
Posts: 13

User manual states:
You can use the comparator output function (ACMP_O) to start or stop the SCT or, more
generally, create an SCT event. To create an SCT event, connect AMP_O as follows:
1. Using the switch matrix, connect ACMP_O to a pin. See Table 203.
2. Using the switch matrix, connect any of the SCT input functions to the same pin.
See Table 107.
The selected SCT input can now monitor the ACMP_O function.

My question now is: do i have to use a real exsiting pin or it is possible to use i.e. P0.6 which is physical not connected to a external pin ?
This would save a physical pin carry a signal i dont need to connect outside of the MCU.

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NXP_Paul's picture
Joined: 2011-10-04
Posts: 161

It is never a good idea to use a pin that does not exist in the device data sheet. Although it may work in some situations, there is no guarantee that it will continue to function correctly in future device revisions.