FN6659 datasheet(23/32 Pages) RENESAS

23 / 32 page

ISL12022

FN6659 Rev.3.01

Page 23 of 32

Oct 24, 2019

DST Day/Week Forward

DstDwFd contains both the Day of the Week and the Week of the

Month data for DST Forward control. DST can be controlled either

by actual date or by setting both the Week of the month and the

Day of the Week. DstDwFdE sets the priority of the Day/Week

over the Date. For DstDwFdE = 1, Day/Week is the priority. You

must have the correct Day of Week entered in the RTC registers

for the Day/Week correction to work properly.

• Bits 0, 1, 2 contain the Day of the week information which sets

the Day of the Week that DST starts. Note that Day of the week

counts from 0 to 6, like the RTC registers. The default for the

DST Forward Day of the Week is 00h (normally Sunday).

• Bits 3, 4, 5 contain the Week of the Month information that sets

the week that DST starts. The range is from 1 to 5, and Week 7

is used to indicate the last week of the month. The default for

the DST Forward Week of the Month is 00h.

DST Date Forward

DstDtfd controls which Date DST begins. The format for the Date

is the same as for the RTC register, from 1 to 31. The default

value for DST forward date is 00h. DstDtFd is only effective if

DstDwFdE = 0.

DST Hour Forward

DstHrFd controls the hour that DST begins. The RTC hour and

DstHrFd registers have the same formats except there is no

Military bit for DST hour. The user sets the DST hour with the

same format as used for the RTC hour (AM/PM or MIL) but

without the MIL bit, and the DST will still advance as if the MIL bit

were there. The default value for DST hour Forward is 00h.

DST REVERSE REGISTERS (24H TO 27H)

DST end (reverse) is controlled by the following DST Registers:

DST Month Reverse

DstMoRv sets the Month that DST ends. The format is the same

as for the RTC register month, from 1 to 12. The default value for

the DST end month is October (10h).

DST Day/Week Reverse

DstDwRv contains both the Day of the Week and the Week of the

Month data for DST Reverse control. DST can be controlled either

by actual date or by setting both the Week of the month and the

Day of the Week. DstDwRvE sets the priority of the Day/Week

over the Date. For DstDwRvE = 1, Day/Week is the priority. You

must have the correct Day of Week entered in the RTC registers

for the Day/Week correction to work properly.

• Bits 0, 1, 2 contain the Day of the week information which sets

the Day of the Week that DST ends. Note that Day of the week

counts from 0 to 6, like the RTC registers. The default for the

DST Reverse Day of the Week is 00h (normally Sunday).

• Bits 3, 4, 5 contain the Week of the Month information that

sets the week that DST ends. The range is from 1 to 5, and

Week 7 is used to indicate the last week of the month. The

default for the DST Reverse Week of the Month is 00h.

DST Date Reverse

DstDtRv controls which Date DST ends. The format for the Date is

the same as for the RTC register, from 1 to 31. The default value

for DST Date Reverse is 00h. The DstDtRv is only effective if the

DwRvE = 0.

DST Hour Reverse

DstHrRv controls the hour that DST ends. The RTC hour and

DstHrFd registers have the same formats except there is no

Military bit for DST hour. The user sets the DST hour with the

same format as used for the RTC hour (AM/PM or MIL) but

without the MIL bit, and the DST will still advance as if the MIL bit

were there. The default value for DST hour Reverse is 00h.

TEMP Registers (TEMP)

The temperature sensor produces an analog voltage output

which is input to an A/D converter and produces a 10-bit

temperature value in degrees Kelvin. TK07:00 are the LSBs of the

code, and TK09:08 are the MSBs of the code. The temperature

result is actually the average of two successive temperature

measurements to produce greater resolution for the temperature

control. The output code can be converted to degrees Centigrade

(°C) by first converting from binary to decimal, dividing by 2, and

then subtracting 273d, as shown in Equation 4:

The practical range for the temp sensor register output is from 446d

to 726d, or -50°C to +90°C. The temperature compensation

function is only guaranteed over -40°C to +85°C. The TSE bit must

be set to “1” to enable temperature sensing.

NPPM Registers (NPPM)

The NPPM value is exactly 2x the net correction required to bring the

oscillator to 0ppm error. The value is the combination of oscillator

Initial Correction (IPPM) and crystal temperature dependent

correction (CPPM).

IPPM is used to compensate the oscillator offset at room

temperature and is controlled by the ITR0 and BETA registers,

which are fixed during factor test.

The CPPM compensates the oscillator frequency fluctuation over

temperature. It is determined by the temperature (T), crystal

curvature parameter (ALPHA), and crystal turnover temperature

(XT0). T is the result of the temp sensor/ADC conversion, whose

decimal result is 2x the actual temperature in Kelvin. ALPHA is

from either the ALPHA (cold) or ALPHAH (hot) register depending

on T, and XT0 is from the XT0 register.

TABLE 22.

TEMP

7654321

TK0L

TK07 TK06 TK05 TK04 TK03 TK02 TK01 TK00

TK0M

0000

TK09 TK08

Temperature in °C

[(TK <9:0>)/2] - 273

(EQ. 4)

FN6659 Datasheet(PDF) 23 Page - Renesas Technology Corp

FN6659 Datasheet(HTML) 23 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

Datasheet Download

Link URL