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-------------------------------------------------------------------------------
Epson 8564JE I2C RTC
-------------------------------------------------------------------------------
This an example capture of I2C traffic from/to an Epson 8564JE I2C RTC chip,
which has a slave address of 0x51 (or 0xa2, if the read/write bit is included).
Logic analyzer setup
--------------------
The logic analyzer used for capturing was a ChronoVu LA8 at a sample rate
of 1MHz. The logic analyzer probes were connected to the RTC chip like this:
Probe RTC chip pin
------------------------
0 (green) SCL
1 (orange) SDA
GND GND
Data
----
The device talking to the RTC was doing the following in an infinite loop:
- Set the RTC to a specific date/time (Nov 22, 2011 - 04:03:54, weekday = 2).
- Read back the current time from the RTC.
This is what the decoded data should look like:
- Setting the date/time:
S Wr:0xa2 A 0x02 A 0x54 A 0x03 A 0x04 A 0x22 A 0x02 A 0x11 A 0x11 A P
- Reading the current date/time:
S Wr:0xa2 A 0x02 A Sr Rd:0xa3 A 0x54 A 0x03 A 0x44 A 0x62 A 0x52 A
0x51 A 0x11 N P
- The abbreviations used above: S = Start, Wr = Write, A = ACK, P = Stop,
Sr = Repeated start, Rd = Read, N = NACK
The sigrok command line used was:
sigrok-cli -d 0:samplerate=1mhz --samples 8388608 \
-p '1=SCL,2=SDA' -o rtc_epson_8564je.sr
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