U4223B Datasheet, PDF (16/18 Pages) ATMEL Corporation – Time-Code Receiver with A/D Converter

U4223B
Information on the Japanese Transmitter
Station: JG2AS
Frequency 40 kHz
Transmitting power 10 kW
Location: Sanwa, Ibaraki
Geographical coordinates: 36_11’ N, 139_51’ E
Time of transmission: permanent
Time frame 1 minute
(index count 1 second)
Time frame
0 5 10 15 20 25 30 35 40 45 50 55 0 5 10
minutes
hours
Example: 18.42 h
P0 40 20 10
da ys
code dut1
Time frame
8 4 2 1 P1
20 10
8 4 2 1 P2
seconds 59 _{0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20}
minutes
hours
Frame-reference marker (FRM)
Position-identifier marker P0
Position identifier marker P1
0.5 s
“1”
0.8 s
“0”
0.2 s
“P”
0.5 second: Binary one
0.8 second: Binary zero
0.2 second: Identifier markers P0...P5
Figure 27.
Modulation
The carrier amplitude is 100% at the beginning of each
second and is switched off after 500 ms (binary one) or
after 800 ms (binary zero).
Time-Code Format
The time-code format consists of 1-minute time frames.
A time frame contains BCD-coded information of
minutes, hours and days. In addition, there are 6 position-
identifier markers (P0 thru P5) and 1 frame-reference
markers (FRM) with reduced carrier amplitude of 800 ms
duration.
16 (18)
Rev. A7, 06-Mar-01