W7500x Reference Manual Version1.1.0
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The pad control supports pull-down, pull-up, input buffer, and summit trigger input buffer.
Refer to ‘Pad Controller (PADCON)’ for more details about each register.
Initial setting Start
GPIO Mode =
GPIO mode Out ?
Yes
Set GPIOxOUTENSET
Set GPIOxOUTENCLR
No
Set PADCON
Set PADCON
Transmit DATA
Receive DATA
END
Figure 14. GPIO Flow chart
Masked access
The masked access feature permits individual bits or multiple bits to be read from or written
to in a single transfer. This avoids software-based read-modify-write operations that are not
thread safe. With the masked access operations, the 16-bit I/O is divided into two halves,
lower byte and upper byte. The bit mask address spaces are defined as two arrays each
containing 256 words.
For example, to set bits[1:0] to 1 and clear bits[7:6] in a single operation, users can carry out
the write to the lower byte mask access address space. The required bit mask is 0xC3, and
users can write the operation as MASKLOWBYTE[0xC3] = 0x03. Refer to Figure 15 below.