UPD78F1146AGB-GAH-AX Renesas Electronics America, UPD78F1146AGB-GAH-AX Datasheet - Page 286

• Manufacturer Part Number: UPD78F1146AGB-GAH-AX
• Description: MCU 16BIT 78K0R/KX3 64-LQFP
• Manufacturer: Renesas Electronics America
• Series: 78K0R/Kx3r

Specifications of UPD78F1146AGB-GAH-AX

• Core Processor: 78K/0R
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: 3-Wire SIO, I²C, LIN, UART/USART
• Peripherals: DMA, LVD, POR, PWM, WDT
• Number Of I /o: 50
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 12K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

7.4.8 Example of watch error correction of real-time counter
correction register.
284
(When DEV = 0)
(When DEV = 1)
Note The correction value is the watch error correction value calculated by using bits 6 to 0 of the watch error
Remarks 1.
The watch can be corrected with high accuracy when it is slow or fast, by setting a value to the watch error
Example of calculating the correction value
The correction value used when correcting the count value of the sub-count register (RSUBC) is calculated by
using the following expression.
Set DEV to 0 when the correction range is −63.1 ppm or less, or 63.1 ppm or more.
Correction value
Correction value
correction register (SUBCUD).
2.
3.
(When F6 = 0) Correction value = {(F5, F4, F3, F2, F1, F0) − 1}
(When F6 = 1) Correction value = − {(/F5, /F4, /F3, /F2, /F1, /F0) + 1}
When (F6, F5, F4, F3, F2, F1, F0) is (*, 0, 0, 0, 0, 0, *), watch error correction is not performed. “*” is 0
or 1.
/F5 to /F0 are bit-inverted values (000011 when 111100).
The correction value is 2, 4, 6, 8, … 120, 122, 124 or −2, −4, −6, −8, … −120, −122, −124.
The oscillation frequency is the subsystem clock (f
It can be calculated from the 32 kHz output frequency of the RTCCL pin or the output frequency of
the RTC1HZ pin
The target frequency is the frequency resulting after correction performed by using the watch error
correction register.
Note
Note
= Number of correction counts in 1 minute = (Oscillation frequency ÷ Target frequency − 1)
= Number of correction counts in 1 minute ÷ 3 = (Oscillation frequency ÷ Target frequency
− 1)
32768
32768
32768 when the watch error correction register is set to its initial value (00H).
CHAPTER 7 REAL-TIME COUNTER
60
60 ÷ 3
User’s Manual U17854EJ9V0UD
SUB
).
2
2