Clock Precision Adjustment Function - Epson RX-8025SA Applications Manual

RX - 8025 SA NB
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8.3. Clock Precision Adjustment Function

The clock precision can be set ahead or behind.
This function can be used to implement a higher-precision clock function, such as by:
• enabling higher clock precision throughout the year by taking seasonal clock precision adjustments into
account in advance, or
• enabling correction of temperature-related clock precision variation in systems that include a temperature
detection function.
∗ Note: Only the clock precision can be adjusted. The adjustments have no effect on the 32.768-kHz output from
the FOUT pin.
8.3.1. Related register
Address
7 Digital Offset
∗) Be sure to set a "0" for any bit whose value is shown above as "0". A zero is returned when any of these bits is read.
• The binary encoded settings in the seven bits from F6 to F0 are used to set the precision of the clock generated
from the 32768-Hz internal oscillator up to ±189.1 × 10
units of ± 3.05 × 10
∗1) When not using this function, be sure to set "0" for bits F6 to F0.
∗2) This function operates every twenty seconds (at 00 seconds, 20 seconds, and 40 seconds within each
minute), which changes the cycle of the periodic interrupts that occur via this timing.
Function".)
8.3.2. Adjustment capacity
1) Adjustment range and resolution
2) Adjustment amount and adjustment value
Adjustment amount
−6
(× 10
−189.10
−186.05
−183.00
•
•
•
−9.15
−6.10
−3.05
OFF
OFF
+3.05
+6.10
+9.15
•
•
•
+183.00
+186.05
+189.10
OFF
OFF
Function bit 7
0
(Default) (0)
−6
.
Adjustment range
−189.1 x 10 −6
to +189.1 x 10
Adjustment data
)
Decimal / Hexadecimal
+63 / 3F h
+62 / 3E h
+61 / 3D h
•
•
•
+4 / 04
+3 / 03
+2 / 02 h
1 / 01 h
0 / 00 h
−1
/ 7F h
−2
/ 7E h
−3
/ 7D h
•
•
•
−60
/ 44 h
−61
/ 43 h
−62
/ 42 h
−63
/ 41 h
−64
/ 40 h
bit 6 bit 5 bit 4
F6 F5 F4
(0) (0) (0)
−6
in the forward (ahead) or reverse (behind) direction, in
Adjustment resolution
−6 ± 3.05 x 10 −6
bit 7 bit 6 bit 5
0 F6 F5
0 0 1
0 0 1
0 0 1
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 1 1
0 1 1
0 1 1
0 1 0
0 1 0
0 1 0
0 1 0
0 1 0
Page - 13
bit 3 bit 2 bit 1
F3 F2 F1
(0) (0) (0)
(See "8.4. Periodic Interrupt
Internal timing of adjustment
Once every 20 seconds
(at "00", "20" and "40" seconds)
bit 4 bit 3 bit 2 bit 1
F4 F3 F2 F1
1 1 1 1
1 1 1 1
1 1 1 0
•
•
•
0 0 1 0
0 0 0 1
0 0 0 1
0 0 0 0
0 0 0 0
1 1 1 1
1 1 1 1
1 1 1 0
•
•
•
0 0 1 0
0 0 0 1
0 0 0 1
0 0 0 0
0 0 0 0
ETM10E-04
bit 0
F0
(0)
bit 0
F0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0