US38024-BAG1 Renesas Electronics America, US38024-BAG1 Datasheet - Page 319

• Manufacturer Part Number: US38024-BAG1
• Description: DEV EVALUATION KIT H8/38024
• Manufacturer: Renesas Electronics America
• Series: H8®r
• Type: MCUr

Specifications of US38024-BAG1

• Contents: 2G (Second-generation) Evaluation Board, HEW debugger support, Cable and CD-ROM
• For Use With/related Products: H8/38024
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

9.5.5
Internal Clock Switching and TCG Operation
Depending on the timing, TCG may be incremented by a switch between different internal clock
sources. Table 9.13 shows the relation between internal clock switchover timing (by write to bits
CKS1 and CKS0) and TCG operation.
When TCG is internally clocked, an increment pulse is generated on detection of the falling edge
of an internal clock signal, which is divided from the system clock (φ) or subclock (φw). For this
reason, in a case like No. 3 in table 9.13 where the switch is from a high clock signal to a low
clock signal, the switchover is seen as a falling edge, causing TCG to increment.
Table 9.13 Internal Clock Switching and TCG Operation
No.
1
2
Clock Levels Before and After
Modifying Bits CKS1 and CKS0
Goes from low level to low level
Goes from low level to high level
Application Notes
TCG Operation
Clock before
switching
Clock after
switching
Count
clock
TCG
Clock before
switching
Clock after
switching
Count
clock
TCG
Rev. 8.00 Mar. 09, 2010 Page 297 of 658
N
N
Write to CKS1 and CKS0
N+1
Write to CKS1 and CKS0
N+1
REJ09B0042-0800
Section 9 Timers
N+2