SH7760 Datasheet, PDF (684/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

• When returning from standby mode to the smart card interface mode:
5. Cancel the standby state.
6. Set the CKE1 bit in SISCR to the value of the output-fixed state at the beginning of standby
(the current SIM_CLK pin state).
7. Write 1 to the CKE0 bit in SISCR to output a clock signal. Clock signal generation begins at
normal duty.
Normal mode
Standby mode
Normal mode
SIM_CLK
(1) (2) (3)
(4)
(5) (6) (7)
Figure 18.11 Procedure for Stopping the Clock and Restarting
18.5.6 Power-On and Clock Output
In order to maintain the clock duty from power-on, the following switching procedure should be
used.
1. The clock output pin is set to an input port as the initial state and is pulled up in the chip.
2. Select the SIM through IPSELR in the PFC.
3. Use the CKE1 bit in SISCR to specify the fixed output.
4. Set the CKE0 bit in SISCR to 1 to start clock output.
18.5.7 Pin Connections
An example of pin connections for the smart card interface is shown in figure 18.12.
In communication with the smart card, transmission and reception are performed using a single
data transmission line. The data transmission line should be pulled up by a resistance on the power
supply V_DDQ side.
When using the clock generated by the smart card interface with the IC card, the SIM_CLK pin
output is input to the CLK pin of the IC card. If an internal clock of the IC card is used, this
connection is not needed.
Rev. 1.0,02/03, page 634 of 1294