HD6412350 Hitachi, HD6412350 Datasheet - Page 637

• Manufacturer Part Number: HD6412350
• Description: (HD6412350 / HD6432351) 16-BIT MICROCONTROLLER
• Manufacturer: Hitachi

Powering On: To secure the clock duty from power-on, the following switching procedure should
be followed.
[1] The initial state is port input and high impedance. Use a pull-up resistor or pull-down resistor
[2] Fix the SCK pin to the specified output level with the CKE1 bit in SCR.
[3] Set SMR and SCMR, and switch to smart card mode operation.
[4] Set the CKE0 bit in SCR to 1 to start clock output.
14.4
The following points should be noted when using the SCI as a Smart Card interface.
Receive Data Sampling Timing and Reception Margin in Smart Card Interface Mode: In
Smart Card Interface mode, the SCI operates on a basic clock with a frequency of 372 times the
transfer rate.
In reception, the SCI samples the falling edge of the start bit using the basic clock, and performs
internal synchronization. Receive data is latched internally at the rising edge of the 186th pulse of
the basic clock. This is illustrated in figure 14-10.
to fix the potential.
Internal
basic
clock
Receive
data (RxD)
Synchro-
nization
sampling
timing
Data
sampling
timing
Usage Notes
Figure 14-10 Receive Data Sampling Timing in Smart Card Mode
0
186 clocks
185
372 clocks
Start bit
371
0
D0
185
371 0
D1
617