National CP3BT26 - Manual (Page 70)

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CP3BT26
14.1.6 Port High Drive Strength Register (PxHDRV)
The PxHDRV register is a byte-wide, read/write register that
controls the slew rate of the corresponding pins. The high
drive strength function is enabled when the corresponding
bits of the PxHDRV register are set. In both GPIO and alter-
nate function modes, the drive strength function is enabled
by the PxHDRV registers. At reset, the PxHDRV registers
are cleared, making the ports low speed.
PxHDRV The PxHDRV bits control whether output pins
are driven with slow or fast slew rate.
0
– Slow slew rate.
1 – Fast slew rate.
14.1.7 Port Alternate Function Select Register
(PxALTS)
The PxALTS register selects which of two alternate func-
tions are selected for the port pin. These bits are ignored
unless the corresponding PxALT bits are set. Each port pin
can be controlled independently.
PxALTS The PxALTS bits select among two alternate
functions. Table 30 shows the mapping of the
PxALTS bits to the alternate functions. Un-
used PxALTS bits must be clear.
7 0
PxHDRV
7 0
PxALTS
Table 30 Alternate Function Select
Port Pin PxALTS = 0 PxALTS = 1
PE0 UART0 RXD0 Reserved
PE1 UART0 TXD0 Reserved
PE2 UART0 RTS Reserved
PE3 UART0 CTS Reserved
PE4 UART0 CKX TB
PE5 SRFS NMI
PF0 MSK TIO1
PF1 MDIDO TIO2
PF2 MDODI TIO3
PF3 MWCS TIO4
PF4 SCK TIO5
PF5 SFS TIO6
PF6 STD TIO7
PF7 SRD TIO8
PG0 RFSYNC Reserved
PG1 RFCE Reserved
PG2 BTSEQ1 SRCLK
PG3 SCLK Reserved
PG4 SDAT Reserved
PG5 SLE Reserved
PG6 WUI10 BTSEQ2
PG7 TA BTSEQ3
PH0 UART1 RXD1 WUI11
PH1 UART1 TXD1 WUI12
PH2 UART2 RXD2 WUI13
PH3 UART2 TXD2 WUI14
PH4 UART3 RXD3 WUI15
PH5 UART3 TXD3 WUI16
PH6 CANRX WUI17
PH7 CANTX Reserved
PJ0 WUI18 Reserved
PJ1 WUI19 Reserved
PJ2 WUI20 Reserved
PJ3 WUI21 Reserved
PJ4 WUI22 Reserved
PJ5 WUI23 Reserved
PJ6 WUI24 Reserved
PJ7 ASYNC WUI9
Table 30 Alternate Function Select
Port Pin PxALTS = 0 PxALTS = 1