DF2505FC26V Renesas Electronics America, DF2505FC26V Datasheet - Page 422

• Manufacturer Part Number: DF2505FC26V
• Description: IC H8S/2505 MCU FLASH 144QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2500r

Specifications of DF2505FC26V

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 26MHz
• Connectivity: I²C, SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 104
• Program Memory Size: 384KB (384K x 8)
• Program Memory Type: FLASH
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 16x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 144-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 11 8-Bit Timers (TMR)
11.8.6
TCNT may increment erroneously when the internal clock is switched over. Table 11.4 shows the
relationship between the timing at which the internal clock is switched (by writing to the CKS1
and CKS0 bits) and the TCNT operation.
When the TCNT clock is generated from an internal clock, the falling edge of the internal clock
pulse is detected. If clock switching causes a change from high to low level, as shown in no. 3 in
table 11.4, a TCNT clock pulse is generated on the assumption that the switchover is a falling
edge. This increments TCNT.
Erroneous incrementation can also happen when switching between internal and external clocks.
Table 11.4 Switching of Internal Clock and TCNT Operation
Rev. 6.00 Sep. 24, 2009 Page 374 of 928
REJ09B0099-0600
No.
1
2
Timing of Switchover
by Means of CKS1 and
CKS0 Bits
Switching from low to
low*
Switching from low to
high*
Switching of Internal Clocks and TCNT Operation
1
2
TCNT Clock Operation
Clock before
switchover
Clock after
switchover
TCNT clock
TCNT
Clock before
switchover
Clock after
switchover
TCNT clock
TCNT
N
N
CKS bit rewrite
N + 1
CKS bit rewrite
N + 1
N + 2