If Read-Modify-Write operations are used on the GPxDAT registers, because of the delay between the
output and the input of the first instruction (I1), the second instruction (I2) will read the old value and
write it back.
GpioDataRegs.GPADAT.bit.GPIO1 = 1 ; I1 performs read-modify-write of GPADAT
GpioDataRegs.GPADAT.bit.GPIO2 = 1 ; I2 also a read-modify-write of GPADAT. ; It gets the old
value of GPIO1 due to the delay
The second instruction will wait for the first to finish its write due to the write-followed-by-read
protection on this peripheral frame. There will be some lag, however, between the write of (I1) and the
GPxDAT bit reflecting the new value (1) on the pin. During this lag, the second instruction will read the
old value of GPIO1 (0) and write it back along with the new value of GPIO2 (1). Therefore, GPIO1 pin
stays low.
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