zeke 693 Posted February 22, 2011 Share Posted February 22, 2011 Today is a good day. 1. I got my 1-wire search algorithm working. I have been able to successfully identify 17 devices on the 1-wire bus. 2. I discovered that DS1821's cannot be searched for on the 1-wire bus. Their presence kills the search algorithm. 3. I got my hardware UART baudrate config routines sorted out. I can run between 9600 and 460800 Baud. 3. I love this Saleae Logic analyzer that I got last Friday. What a life saver! Here's a screenshot of it showing 10 1-Wire sensors during the search routine. Here's what the output looks like for 17 sensors: PacketId, Time[s], Detail, [data] 0,0,Reset Pulse 0,0.0005115,Presence Pulse 1,0.00097,Reset Pulse 1,0.001481,Presence Pulse 1,0.001944,Search Rom Command, 0xF0 1,0.002529,ROM Family Code, 0x10 1,0.004464,ROM Code, 0x0008022E69B2 1,0.016032,ROM CRC, 0x2C 2,0.01798,Reset Pulse 2,0.01849,Presence Pulse 2,0.0189535,Search Rom Command, 0xF0 2,0.0195385,ROM Family Code, 0x10 2,0.021476,ROM Code, 0x0008022E6C86 2,0.033045,ROM CRC, 0xCF 3,0.0349955,Reset Pulse 3,0.035506,Presence Pulse 3,0.0359695,Search Rom Command, 0xF0 3,0.036554,ROM Family Code, 0x28 3,0.0384905,ROM Code, 0x000002E13980 3,0.0500605,ROM CRC, 0x0A 4,0.0520075,Reset Pulse 4,0.052518,Presence Pulse 4,0.0529815,Search Rom Command, 0xF0 4,0.053566,ROM Family Code, 0x28 4,0.0555025,ROM Code, 0x0000030F101A 4,0.0670725,ROM CRC, 0x88 5,0.06902,Reset Pulse 5,0.0695305,Presence Pulse 5,0.0699935,Search Rom Command, 0xF0 5,0.070579,ROM Family Code, 0x28 5,0.072516,ROM Code, 0x0000030F08EB 5,0.084089,ROM CRC, 0x8F 6,0.086038,Reset Pulse 6,0.086549,Presence Pulse 6,0.0870115,Search Rom Command, 0xF0 6,0.0875965,ROM Family Code, 0x1C 6,0.089529,ROM Code, 0x00000537A27F 6,0.101104,ROM CRC, 0x09 7,0.1030515,Reset Pulse 7,0.103562,Presence Pulse 7,0.1040255,Search Rom Command, 0xF0 7,0.104611,ROM Family Code, 0x1C 7,0.1065445,ROM Code, 0x0000052C4D7F 7,0.1181165,ROM CRC, 0x10 8,0.120063,Reset Pulse 8,0.1205735,Presence Pulse 8,0.121037,Search Rom Command, 0xF0 8,0.1216225,ROM Family Code, 0x22 8,0.123555,ROM Code, 0x0000002A3ACB 8,0.1351255,ROM CRC, 0xA0 9,0.137074,Reset Pulse 9,0.137585,Presence Pulse 9,0.1380485,Search Rom Command, 0xF0 9,0.138634,ROM Family Code, 0x22 9,0.1405665,ROM Code, 0x0000002A702F 9,0.152135,ROM CRC, 0x01 10,0.1540815,Reset Pulse 10,0.1545915,Presence Pulse 10,0.1550545,Search Rom Command, 0xF0 10,0.15564,ROM Family Code, 0x01 10,0.157573,ROM Code, 0x000013B1FBEC 10,0.1691465,ROM CRC, 0x0F 11,0.1710955,Reset Pulse 11,0.1716065,Presence Pulse 11,0.17207,Search Rom Command, 0xF0 11,0.172655,ROM Family Code, 0x01 11,0.174589,ROM Code, 0x000013B22BDC 11,0.1861595,ROM CRC, 0x34 12,0.188107,Reset Pulse 12,0.188617,Presence Pulse 12,0.18908,Search Rom Command, 0xF0 12,0.1896645,ROM Family Code, 0x2D 12,0.1915995,ROM Code, 0x00000209FB06 12,0.203172,ROM CRC, 0x6F 13,0.205121,Reset Pulse 13,0.2056315,Presence Pulse 13,0.2060945,Search Rom Command, 0xF0 13,0.2066795,ROM Family Code, 0x2D 13,0.208614,ROM Code, 0x0000020A0E5F 13,0.220185,ROM CRC, 0x2B 14,0.2221335,Reset Pulse 14,0.2226435,Presence Pulse 14,0.2231065,Search Rom Command, 0xF0 14,0.223692,ROM Family Code, 0x43 14,0.2256255,ROM Code, 0x0000001E305C 14,0.2371975,ROM CRC, 0x7A 15,0.2391465,Reset Pulse 15,0.2396565,Presence Pulse 15,0.24012,Search Rom Command, 0xF0 15,0.2407055,ROM Family Code, 0x43 15,0.2426395,ROM Code, 0x0000001E286B 15,0.2542075,ROM CRC, 0x50 16,0.256154,Reset Pulse 16,0.2566645,Presence Pulse 16,0.2571275,Search Rom Command, 0xF0 16,0.257713,ROM Family Code, 0x23 16,0.259645,ROM Code, 0x000000F0D232 16,0.271214,ROM CRC, 0x87 ,0.273162,Reset Pulse ,0.273673,Presence Pulse ,0.2741355,Search Rom Command, 0xF0 ,0.2747205,ROM Family Code, 0x23 ,0.2766535,ROM Code, 0x000000F0BCC3 ,0.2882255,ROM CRC, 0x71 Today is a good day. Next on the list is the dreaded printf(). gatesphere and jsolarski 2 Quote Link to post Share on other sites
NatureTM 100 Posted February 22, 2011 Share Posted February 22, 2011 This seems interesting, but I guess I don't have the experience to know how and when it would be used. So you attach this to the 1-wire bus and basically say, "is accelerometer here?" "Here!" "Is there an rtc here? "Here!" Could you use this for salvage or repair, or do you have a specific application in mind? Quote Link to post Share on other sites
zeke 693 Posted February 22, 2011 Author Share Posted February 22, 2011 Well, the answer is both yes and no. Yes to how it's being said. No to what devices are being queried. Dallas Semiconductor (now Maxim) created a family of devices that talk 1-wire protocol. Here's a copy/paste from their website: The 1-Wire and iButton products combine the single-contact 1-Wire serial interface with nonvolatile memory, mixed-signal, and secure authentication functions into products that serve a broad range of applications. 1-Wire products are manufactured in traditional IC packaging. iButton products are available in a unique, robust stainless steel package. But how would I use these devices? Well, I have been trying to land a contract with a local company that uses a truck load of ds18b20's in their product. We're talking in the order of 400 to 500 temp sensors in one installation. Every single one of these sensors is on a single 1-wire bus. They monitor the temperature of big piles of stuff to prevent spoilage and whatnot. I'm trying to prove to myself that I can do this and somehow land a job. Wouldn't that be cool to walk into a job interview and do a hands on demo? Scary but cool. Did I answer your question? NatureTM 1 Quote Link to post Share on other sites
NatureTM 100 Posted February 22, 2011 Share Posted February 22, 2011 Yeah, answered well. I'd think your effort would go a long way in an interview. Hopefully they can appreciate it. Good luck! Quote Link to post Share on other sites
zeke 693 Posted February 22, 2011 Author Share Posted February 22, 2011 Thanks! My mentor that I have to "man up" and try to do a demo for these guys once I get printf() working on this F5438. It's amazing how crippling fear is. I have to remember that it is a liar also. Quote Link to post Share on other sites
bluehash 1,581 Posted February 23, 2011 Share Posted February 23, 2011 Nice job. Changed your subject a little for members browsing the forums. Quote Link to post Share on other sites
zeke 693 Posted February 23, 2011 Author Share Posted February 23, 2011 No problem. Quote Link to post Share on other sites
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