--- In lpc2000@yahoogroups.com, "Dave" <dgsomerton@w...> wrote: > Hello, > > Some weird things happen when using PORT 1. > > Firstly, make sure the debug and trace functions are disabled. > > regVal = PINSEL2; > regVal &= ~((1 << 2) | (1 << 3)); > PINSEL2 = regVal; > > Next, set the pins used as outputs to become outputs, and drive their > outputs high. > > regVal = (1 << 31) | (1 << 26) | (1 << 24); > IODIR1 = regVal; > IOPIN1 = regVal; > > Constantly read the pin values and display. > > port1.26 is always flickering (i.e. on/off) when read. > the output does not change, it remains driven high, just the > readback from IOPIN1 shows this. > > Further, a circuit to detect switch closures uses 8 bits of port 0 and > 8 bits of port 1. The inputs to port 1 read as expected, but the > inputs to port 1 are always 'high'. Can this be explained? > > Dave Typo: > 8 bits of port 1. The inputs to port 1 read as expected, but the > inputs to port 1 are always 'high'. Can this be explained? should be > 8 bits of port 1. The inputs to port 0 read as expected, but the > inputs to port 1 are always 'high'. Can this be explained? Dave
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Re: GPIO Port 1 (2132)
2005-07-19 by Dave
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