h8s-2635 Renesas Electronics Corporation., h8s-2635 Datasheet - Page 589

• Manufacturer Part Number: h8s-2635
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

In a receive operation, an RXI interrupt request is generated when the RDRF flag in SSR is set to
1. If the RXI request is designated beforehand as a DTC activation source, the DTC will be
activated by the RXI request, and transfer of the receive data will be carried out. The RDRF flag is
cleared to 0 automatically when data transfer is performed by the DTC. If an error occurs, an error
flag is set but the RDRF flag is not. Consequently, the DTC is not activated, but instead, an ERI
interrupt request is sent to the CPU. Therefore, the error flag should be cleared.
Notes: For block transfer mode, see section 13.4, SCI Interrupts.
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.
[5] Make the transition to the software standby state.
[6] Exit the software standby state.
[7] Write 1 to the CKE0 bit in SCR and output the clock. Signal generation is started with the
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.
During this interval, clock output is fixed at the specified level, with the duty preserved.
When returning to smart card interface mode from software standby mode
normal duty.
* The DTC is not implemented in the H8S/2635 and H8S/2634.
Operation in GSM Mode
Rev. 6.00 Feb 22, 2005 page 529 of 1484
Section 14 Smart Card Interface
REJ09B0103-0600