HD64F3437STF16V Renesas Electronics America, HD64F3437STF16V Datasheet - Page 259

• Manufacturer Part Number: HD64F3437STF16V
• Description: MCU 3/5V 60K PB-FREE 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300r

Specifications of HD64F3437STF16V

• Core Processor: H8/300
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: Host Interface, I²C, SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 74
• Program Memory Size: 60KB (60K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Reading TCNT and TCSR: The read addresses are H'FFA8 for TCSR and H'FFA9 for TCNT, as
indicated in table 11.3.
These two registers are read like other registers. Byte access instructions can be used.
Table 11.3 Read Addresses of TCNT and TCSR
Read Address
H'FFA8
H'FFA9
11.3
11.3.1
The watchdog timer function begins operating when software sets the WT/IT and TME bits to 1 in
TCSR. Thereafter, software should periodically rewrite the contents of the timer counter (normally
by writing H'00) to prevent the count from overflowing. If a program crash allows the timer count
to overflow, the entire chip is reset for 518 system clocks (518 ø), or an NMI interrupt is
requested. Figure 11.3 shows the operation.
NMI requests from the watchdog timer have the same vector as NMI requests from the NMI pin.
Avoid simultaneous handling of watchdog timer NMI requests and NMI requests from pin NMI.
A reset from the watchdog timer has the same vector as an external reset from the RES pin. The
reset source can be determined by the XRST bit in SYSCR.
TCNT count
H'FF
H'00
Operation
Watchdog Timer Mode
WT/IT = 1
TME = 1
Figure 11.3 Operation in Watchdog Timer Mode
H'00 written
to TCNT
Register
TCSR
TCNT
OVF = 1
WDT overflow
Reset
518 ø
WT/IT = 1
TME = 1
H'00 written
to TCNT
Time t
227