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Signal Descriptions
MFR4200 Data Sheet, Rev. 0
Freescale Semiconductor
41
IF_SEL1 is the CC external interface selection input signal. Refer to
Table 2-1
for the selection coding.
NOTE
IF_SEL[0:1] signals are inputs during the internal reset sequence and are
latched by the internal reset signal level.
While the IF_SEL1 level is being latched, the output drive control is
disabled and the internal pulldown resistor is connected to the pin.
As IF_SEL[0:1] signals share pins with Physical Layer Interface signals,
pullup/down devices must be used for the selection. Recommended
pullup/down resistor values for the IF_SEL[0:1] inputs are given in
Section 2.4.2, “Recommended Pullup/down Resistor Values
”.
2.2.3.15
TXD_BG2/TXD2_485 — PHY Transmit Data 2, RS485 Transmit Data 2
The function of this pin is selected by the SCM[0:1] bits in the MCR0 register. Refer to
Section 3.2.3.2.1,
“Module Configuration Register 0 (MCR0)
” for more information.
TXD_BG[1:2] are bus driver transmit data output signals if the FlexRay Optical/Electrical PHY is
configured:
TXD_BG1 is the output of the CC to Physical Layer Channel 1.
TXD_BG2 is the output of the CC to Physical Layer Channel 2.
TXD[1:2]_485 are bus driver transmit data output signals if the RS485 Driver type is configured:
TXD1_485 is the output of the CC to the Physical Layer Channel 1.
TXD2_485 is the output of the CC to the Physical Layer Channel 2.
2.2.3.16
BGEN[1:2] — Bus Guardian Enable
The CC monitors the schedule of Bus Guardians operations by checking the BGEN[1:2] input signals
provided by Bus Guardians:
BGEN1 is the input from the Physical Layer Channel 1 to the CC.
BGEN2 is the input from the Physical Layer Channel 2 to the CC.
If the RS485 Driver type is configured, the BGEN[1:2] inputs are not used and may be left open, but it is
recommended to connect these pins to the logic "0" or logic "1" level either by enabling either pullup or
pulldown resistors or by using external components. The pins can be configured to enable or disable either
pullup or pulldown resistors on the pins.
2.2.3.17
CLKOUT — Clock Output
CLKOUT is an external continuous clock output signal. The frequency of CLKOUT is selected by the
CLK_S[0:1] pins. The CLKOUT signal is always active after power-up of the CC, in all CC states
including the hard reset state. The pin can be configured to provide either high or reduced output drive.