X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=i2c%2Frtc_dallas_ds1307%2FREADME;fp=i2c%2Frtc_dallas_ds1307%2FREADME;h=2cd514555eb0073c4ce01ae97133f520de2ad2af;hb=466b3bd018ba1363f8bb24dde5ae5dd4b8bd66b0;hp=0000000000000000000000000000000000000000;hpb=3001a69503430dcf32c88b3742e86ec37d33db1a;p=sigrok-dumps.git diff --git a/i2c/rtc_dallas_ds1307/README b/i2c/rtc_dallas_ds1307/README new file mode 100644 index 0000000..2cd5145 --- /dev/null +++ b/i2c/rtc_dallas_ds1307/README @@ -0,0 +1,44 @@ +------------------------------------------------------------------------------- +Dallas DS1307 RTC Clock +------------------------------------------------------------------------------- + +This is a capture of data ouput from a Dallas DS1307 RTC module using: + + - hwclock -f /dev/rtc1 --systohc && { while true; hwclock -f /dev/rtc1; done } + +Details: + - DS1307 datasheet: http://sparkfun.com/datasheets/Components/DS1307.pdf + + +Logic analyzer setup +-------------------- + +The logic analyzer used was Open Bench Logic Sniffer (at 20kHz): + + Probe DS1307 pin + ------------------------- + 0 SCL + 1 SDA + + +Data +---- + +This is what the decoded data should look like: + + - Setting the date/time: + S Wr:0x68 A 0x16 A 0x35 A 0x18 A 0x01 A 0x10 A 0x03 A 0x13 A P + + - Reading the current date/time: + S Wr:0x68 A 0x00 A Sr Rd:0x68 A 0x16 A 0x35 A 0x18 A 0x01 A 0x10 A + 0x03 A 0x13 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 --driver=ols:conn=/dev/ttyACM0 -d samplerate=200khz \ + --samples=24576 -p 0=SCL,1=SDA --triggers SDA=0 -o +