HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 528

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

•
Use the following procedure to secure the clock duty cycle after powering on.
1.
2.
3.
4.
2. Write 0 to the TE and RE bits in the serial control register (SCR) to stop transmit/receive
3. Write 0 to the CKE0 bit in SCR to stop the clock.
4. Wait for one serial clock cycle. During this period, the duty cycle is preserved and clock
5. Write H'00 to the serial mode register (SMR) and smart card mode register (SCMR).
6. Make the transition to the software standby state.
Returning from software standby mode to smart card interface mode
1. Clear the software standby state.
2. Set the CKE1 bit in SCR to the value for the fixed output state at the start of software
3. Set smart card interface mode and output the clock. Clock signal generation is started
The initial state is port input and high impedance. Use pull-up or pull-down resistors to fix
the potential.
Fix at the output specified by the CKE1 bit in SCR.
Set SMR and SCMR, and switch to smart card interface mode operation.
Set the CKE0 bit in SCR to 1 to start clock output.
operations. At the same time, set the CKE1 bit to the value for the fixed output state in
software standby mode.
output is fixed at the specified level.
standby (the current P94 pin state).
with the normal duty cycle.
(1)(2)(3)
Figure 14.9 Procedure for Stopping and Restarting the Clock
Normal operation
(4) (5)(6)
Software standby
mode
518
(1) (2)(3)
Normal operation