LAPIS Semiconductor ML610421, User Manual, Page: 215 / 437

ML610Q421/ML610Q422/ML610421 User’s Manual
Chapter 14 UART
14 – 20
P02 is an input-only port, so there is no need to specify data direction (i.e. input or output).
Data setting to P02C1 bit and P02C0 bit, depend on the application circuit connected to P02.
Reg. name P0CON1 register (Address: 0F207H)
Bit 7 6 5 4 3 2 1 0
Bit name
- - - - P03C1 P02C1 P01C1 P00C1
Data - - - - * $ * *
Reg. name P0CON0 register (Address: 0F206H)
Bit 7 6 5 4 3 2 1 0
Bit name
- - - - P03C0 P02C0 P01C0 P00C0
Data - - - - * $ * *
Data of P02D bit (bit2 of P0D register) do not affect to the UART function, so don’t care the data for the function.
Reg. name P0D register (Address: 0F204H)
Bit 7 6 5 4 3 2 1 0
Bit name
- - - - P03D P02D P01D P00D
Data - - - - * ** * *
* : Bit not related to the UART(using P43 and P02) function
** : Don’t care the data
$ : Arbitrarily
Note:
The receive pin (RXD0) is selected by U0RSEL bit(bit4 of UA0MOD0 register). Setting the bit to “0” (initial
value) selects P02 pin and setting the bit to “1” selects P43 pin.
Even if P42 is specified as RXD0 by P42MD1 bit, P42MD0 bit, P42C1 bit, P42C0 bit and P42IDR bit, setting
“0” to U0RSEL bit has priority to select P02 pin as the RXD0.
P02(Port 0) is an input-only port, does not have registers that can select data direction(input or output) or
mode(primary or secondary function).