UPD70F3737GC-UEU-AX Renesas Electronics America, UPD70F3737GC-UEU-AX Datasheet - Page 409

• Manufacturer Part Number: UPD70F3737GC-UEU-AX
• Description: MCU 32BIT V850ES/JX3-L 100-LQFP
• Manufacturer: Renesas Electronics America
• Series: V850ES/Jx3-Lr

Specifications of UPD70F3737GC-UEU-AX

• Package / Case: *
• Voltage - Supply (vcc/vdd): 2.2 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Speed: 20MHz
• Number Of I /o: 84
• Core Processor: RISC
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Program Memory Size: 128KB (128K x 8)
• Data Converters: A/D 12x10b, D/A 2x8b
• Oscillator Type: Internal
• Peripherals: DMA, LVD, PWM, WDT
• Connectivity: CSI, EBI/EMI, I²C, UART/USART
• Core Size: 32-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

10.4 Operation
10.4.1 Operation as watch timer
using time intervals of 0.25 or 0.5 seconds with the subclock (32.768 kHz) or main clock.
cleared to 0, the 11-bit prescaler and 5-bit counter are cleared and the count operation stops.
operating at the same time as the interval timer. At this time, an error of up to 15.6 ms may occur for the watch timer,
but the interval timer is not affected.
BGCS00 bits, the 8-bit comparison value using the PRSCM0 register, and the count clock frequency (f
watch timer to 32.768 kHz.
PRSCM0 register.
The watch timer generates an interrupt request signal (INTWT) at fixed time intervals. The watch timer operates
The count operation starts when the WTM.WTM1 and WTM.WTM0 bits are set to 11. When the WTM0 bit is
The time of the watch timer can be adjusted by clearing the WTM1 bit to 0 and then the 5-bit counter when
If the main clock is used as the count clock of the watch timer, set the count clock using the PRSM0.BGCS01 and
When the PRSM0.BGCE0 bit is set (1), f
f
To set f
<1> Set N = f
<2> When the value resulting from rounding up the first decimal place of N is even, set N before the roundup as
<3> Repeat <2> until N is odd or m = 3.
<4> Set the value resulting from rounding up the first decimal place of N to the PRSCM0 register and m to the
Example: When f
Remark m: Division value (set value of BGCS01 and BGCS00 bits) = 0 to 3
BRG
f
BRG
can be calculated by the following expression.
N/2 and m as m + 1.
BGCS01 and BGCS00 bits.
= f
BRG
X
N: Set value of PRSCM0 register = 1 to 256
f
/(2
<1> N = 4,000,000/65,536 = 61.03…, m = 0
<2>, <3> Because N (round up the first decimal place) is odd, N = 61, m = 0.
<4> Set value of PRSCM0 register: 3DH (61), set value of BGCS01 and BGCS00 bits: 00
At this time, the actual f
f
X
BRG
: Main clock oscillation frequency
to 32.768 kHz, perform the following calculation and set the BGCS01 and BGCS00 bits and the
X
However, N = 256 when PRSCM0 register is set to 00H.
m+1
/65,536. Set m = 0.
= f
= 32.787 kHz
× N)
X
X
/(2
= 4.00 MHz
m+1
× N) = 4,000,000/(2 × 61)
BRG
CHAPTER 10 WATCH TIMER FUNCTIONS
Preliminary User’s Manual U18953EJ1V0UD
frequency is as follows.
BRG
is supplied to the watch timer.
BRG
) of the
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