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Based on kernel version 3.16. Page generated on 2014-08-06 21:41 EST.

1	Kernel driver w1_ds2423
2	=======================
3	
4	Supported chips:
5	  * Maxim DS2423 based counter devices.
6	
7	supported family codes:
8		W1_THERM_DS2423	0x1D
9	
10	Author: Mika Laitio <lamikr@pilppa.org>
11	
12	Description
13	-----------
14	
15	Support is provided through the sysfs w1_slave file. Each opening and
16	read sequence of w1_slave file initiates the read of counters and ram
17	available in DS2423 pages 12 - 15.
18	
19	Result of each page is provided as an ASCII output where each counter
20	value and associated ram buffer is outpputed to own line.
21	
22	Each lines will contain the values of 42 bytes read from the counter and
23	memory page along the crc=YES or NO for indicating whether the read operation
24	was successful and CRC matched.
25	If the operation was successful, there is also in the end of each line
26	a counter value expressed as an integer after c=
27	
28	Meaning of 42 bytes represented is following:
29	 - 1 byte from ram page
30	 - 4 bytes for the counter value
31	 - 4 zero bytes
32	 - 2 bytes for crc16 which was calculated from the data read since the previous crc bytes
33	 - 31 remaining bytes from the ram page
34	 - crc=YES/NO indicating whether read was ok and crc matched
35	 - c=<int> current counter value
36	
37	example from the successful read:
38	00 02 00 00 00 00 00 00 00 6d 38 00 ff ff 00 00 fe ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
39	00 02 00 00 00 00 00 00 00 e0 1f 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
40	00 29 c6 5d 18 00 00 00 00 04 37 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=408798761
41	00 05 00 00 00 00 00 00 00 8d 39 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff crc=YES c=5
42	
43	example from the read with crc errors:
44	00 02 00 00 00 00 00 00 00 6d 38 00 ff ff 00 00 fe ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
45	00 02 00 00 22 00 00 00 00 e0 1f 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=NO
46	00 e1 61 5d 19 00 00 00 00 df 0b 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=NO
47	00 05 00 00 20 00 00 00 00 8d 39 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff crc=NO
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