H8S-2350 RENESAS [Renesas Technology Corp], H8S-2350 Datasheet - Page 670

• Manufacturer Part Number: H8S-2350
• Description: 16-Bit Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 14 Smart Card Interface
14.3.7
Switching the Mode
When switching between smart card interface mode and software standby mode, the following
switching procedure should be followed in order to maintain the clock duty.
[1] Set the data register (DR) and data direction register (DDR) corresponding to the SCK pin to
[2] Write 0 to the TE bit and RE bit in the serial control register (SCR) to halt transmit/receive
[3] Write 0 to the CKE0 bit in SCR to halt the clock.
[4] Wait for one serial clock period.
During this interval, clock output is fixed at the specified level, with the duty preserved.
[5] Write H'00 to SMR and SCMR.
[6] Make the transition to the software standby state.
[7] Exit the software standby state.
[8] Set the CKE1 bit in SCR to the value for the fixed output state (current SCK pin state) when
[9] Set smart card interface mode and output the clock. Signal generation is started with the
Rev. 3.00 Sep 15, 2006 page 636 of 988
REJ09B0330-0300
When changing from smart card interface mode to software standby mode:
the value for the fixed output state in software standby mode.
operation. At the same time, set the CKE1 bit to the value for the fixed output state in software
standby mode.
When returning to smart card interface mode from software standby mode:
software standby mode is initiated.
normal duty.
Operation in GSM Mode
[1] [2] [3]
Normal operation
Figure 14.9 Clock Halt and Restart Procedure
[4] [5] [6]
Software
standby
[7] [8] [9]
Normal operation