DF2437FV Renesas Electronics America, DF2437FV Datasheet - Page 442

• Manufacturer Part Number: DF2437FV
• Description: IC H8S/2437 MCU FLASH 128QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2400r

Specifications of DF2437FV

• Core Processor: H8S/2600
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: I²C, SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 85
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 128-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

13.4.3
The timer connection, TMR1, and FRT can be used to measure the period of an IHI signal divided
waveform. Since the TMR1 can be cleared by a rising edge of the inverted IVI signal, the rise and
fall of the IHI signal divided waveform can be synchronized with the IVI signal. This enables
period measurement to be carried out efficiently. Figure 13.8 shows a block diagram for the period
measurement of the 8-bit timer divided waveform.
To measure the period of an IHI signal divided waveform, TCNT of the TMR1 is set to count the
external clock (IHI signal) pulses and to be cleared on the rising edge of the external reset signal
(inverse of the IVI signal). The value to be used as the division ratio is written to TCORA, and the
TMO output method is specified by the OS bit in TCSR.
Examples of TCR and TCSR settings of the TMR1 and FRT are shown in table 13.7, and the
timing chart for measurement of the IVI signal and IHI signal divided waveform periods is shown
in figure 13.9. The period of the IHI signal divided waveform is given by (ICRD(3) – ICRD(2)) ×
resolution.
Rev.2.00 May. 28, 2009 Page 402 of 732
REJ09B0059-0200
Figure 13.8 Block Diagram for Measurement of 8-Bit Timer Divided Waveform Period
Internal clock
ICRB
FRC
Measurement of 8-Bit Timer Divided Waveform Period
Capture
FRT
Control logic
FTIB
TMO
Control logic
IVI signal
Clear
CMA
CMB
Clear
TMR1
Comparator A
Comparator B
TCORA
TCORB
TCNT
Clock
IHI signal