HD6477021X20V Renesas Electronics America, HD6477021X20V Datasheet - Page 347

• Manufacturer Part Number: HD6477021X20V
• Description: MCU 5V 32K PB-FREE 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7020r

Specifications of HD6477021X20V

• Core Processor: SH-1
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: EBI/EMI, SCI
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: OTP
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• 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: -
• Data Converters: -

Table 12.1 Pin Configuration
Pin
Watchdog timer overflow
12.1.4
Table 12.2 summarizes the three WDT registers. They are used to select the clock, switch the
WDT mode, and control the reset signal.
Table 12.2
Name
Timer
control/status
register
Timer counter
Reset
control/status
register
Notes: 1. Write by word transfer. It cannot be written in byte or long word.
12.2
12.2.1
The TCNT is an eight-bit readable and writable upcounter. The TCNT differs from other registers
in that it is more difficult to write. See section 12.2.4, Register Access, for details. When the timer
enable bit (TME) in the timer control/status register (TCSR) is set to 1, the timer counter starts
counting pulses of an internal clock source selected by clock select bits 2–0 (CKS2–CKS0) in the
TCSR. When the value of the TCNT overflows (changes from H'FF–H'00), a watchdog timer
overflow signal (WDTOVF) or interval timer interrupt (ITI) is generated, depending on the mode
selected in the WT/IT bit of the TCSR. The TCNT is initialized to H'00 by a reset and when the
TME bit is cleared to 0. It is not initialized in the standby mode.
2. Read by byte transfer. It cannot be read in word or long word.
3. Only 0 can be written in bit 7 to clear the flag.
Register Configuration
Register Descriptions
Timer Counter (TCNT)
WDT Registers
Abbreviation
TCSR
TCNT
RSTCSR
Abbreviation
WDTOVF
R/W
R/(W)*
R/W
R/(W)*
I/O
O
3
3
Initial Value
H'18
H'00
H'3F
Function
Outputs the counter overflow signal in
the watchdog mode
Write*
H'5FFFFB8
H'5FFFFBA
1
Address
RENESAS 329
Read*
H'5FFFFB8
H'5FFFFB9
H'5FFFFBB
2