DF2117VT20V Renesas Electronics America, DF2117VT20V Datasheet - Page 429

• Manufacturer Part Number: DF2117VT20V
• Description: MCU 16BIT FLASH 3V 160K 144-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2100r

Specifications of DF2117VT20V

• Core Processor: H8S/2600
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: FIFO, I²C, LPC, SCI, SmartCard
• Peripherals: POR, PWM, WDT
• Number Of I /o: 112
• Program Memory Size: 160KB (160K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 144-TQFP, 144-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

13.9.5
TCNT may increment erroneously when the internal clock is switched over. Table 13.8 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 13.8, a TCNT clock pulse is generated on the assumption that the switchover is a falling
edge, and TCNT is incremented.
Erroneous incrementation can also happen when switching between internal and external clocks.
Table 13.8 Switching of Internal Clocks and TCNT Operation
No.
1
2
Timing of Switchover
by Means of CKS1
and CKS0 Bits
Clock switching from low
to low level*
Clock switching from low
to high level*
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
Rev. 2.00 Sep. 28, 2009 Page 387 of 994
N + 1
CKS bit rewrite
N + 1
N + 2
REJ09B0452-0200