h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 458

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 13 Serial Communication Interface (SCI)
• Usage Note: To prevent low-level output occurred when switching the SCK pin to port pin,
1. End of serial data transmission
2. TE bit = 0
3. CKE1 bit = 1
4. C/A bit = 0 ... switchover to port output
5. CKE1 bit = 0
Rev. 2.00 Dec. 05, 2005 Page 420 of 724
REJ09B0200-0200
follow the procedure described below.
As this sample procedure temporarily places the SCK pin in the input state, the SCK/port pin
should be pulled up beforehand with an external circuit.
With DDR = 1, DR = 1, C/A = 1, CKE1 = 0, CKE0 = 0, and TE = 1, make the following
settings in the order shown.
SCK/port
Data
TE
C/A
CKE1
CKE0
Figure 13.39 Operation when Switching from SCK Pin to Port Pin
Bit 6
(Example of Preventing Low-Level Output)
Bit 7
1. End of transmission
2. TE = 0
3. CKE1 = 1
4. C/A = 0
High-level output
5. CKE1 = 0