Further shipping… I2C problems

So I received my new order with a few more sensors, memory sockets, and a new set of cables that were Female/Female. Not only did I have problems with the shipping involving the first order going to the wrong city and being REALLY slow…. THIS TIME I purposely switched to FedEx and bumped it to Next Day delivery because I was tired of waiting for things. My package “went walking in Memphis” or perhaps went on safari in the Jungle Room or something. Apparently FedEx had mechanical problems and as a result my package did not leave the Memphis hub until after the time it was already due to be delivered to my door in California. It was thus NOT next day.

Once I finally received it I figured I’d start off with attempting to read the real time clock chips I have using I2C. The PIC32 has built in hardware commands for accessing I2C so normally this shouldn’t be too difficult following the address strings and writing/reading according to the patterns required in the datasheet. This even further so since I managed to get it working on a PIC24 in the past so I’m not completely clueless in the I2C (or SPI or One Wire) world.

I tried a few things making adjustments and generally did not get anywhere. I’ve checked the voltage on the bus and I do indeed have 5 volts. At first I had only 4.8 volts due to the LCD backlight sucking most of the power off the USB port. I dug out the AC adapter I ordered and plugged it into the system and brought the power up the rest of the way and all was normal voltage wise. As I change the resistors and play with the speed of the bus I go from having NO responses to 0x00 responses to 0xFF responses… to 0x01 responses. ONCE I managed to get some numbers out of it that made absolutely no sense at all. They were returning things like 80 for the seconds and some 140 something for other things… 12 for others that should have been something else. It was just all over the place.

I don’t have an oscilloscope to try to look at anything closer and one of my co-workers said he had an old scope but no leads anymore. Since I knew I’d need to order some new leads if I borrowed his scope I started digging around to see what’s out there to see what I wanted to do. I have since that expedition ordered a logic analyzer that supposedly I can decode/time/process/log/graph/whatever all the various I2C channel data. I’m not entirely sure how exactly I do this still since documentation is a bit rough to come by properly on the internet the is explicitly involving I2C and the capabilities. It generally just mentions these things in passing and shows a screen shot.

In addition I run into a possible problem having Windows XP x64 bit and having had to host my PIC32 development work out of a virtualized XP 32 bit with USB pass through and trying to get some drivers installed so this should be fun.

I’m still waiting for the logic analyzer to ship. I ordered it on the 9th (here and at the seller’s location during their business day). The seller has updated the order status to “processing”. They indicate they typically ship within 1 to 3 business days. They are located in China so it’s “tomorrow” there now. It was ordered with UPS Worldwide Express delivery so it is SUPPOSED TO be “next day” delivery. I’m not sure how the next day works exactly in terms of time zones. Is it next day shippers time zone? Next day from calendar time/date between both of us? I just don’t know how that one works since I’ve only had the one package from Bulgaria and a couple more from Thailand in this project and neither was the spendy UPS.

I’m guessing if it ships “today” in China it will ship Thursday the 12th China time while it is still Wednesday the 11th here. It will then arrive to me Friday the 13th (sheesh) US time giving them about a day and a half for delivery. I could be entirely wrong though…. doubt it. I just don’t see how they could get something from China to Northern California that quickly. I mean they have what appears to be a 3 hour flight inside China to another airport and from there straight on to San Francisco for 12 hours. With time zone differences etc it appears that flights leaving there around 4 PM China time arrive in the US in San Francisco at 11:30 in the morning “the same day” Pacific Time. From there it would be a normal in the US “overnight” delivery. Actual flights are probably 4-8 hours later. It would catch a smaller flight to Sacramento overnight and then continuing onwards up to where I live for delivery the following day since they seem to fly UPS packages into the local airport whether it’s ground or next day air etc from Sacramento.

Guess we’ll see what happens. I’m guessing I’ll need to sign for it since it’s an international delivery. Everything I’ve gotten international so far required a signature. Other people I’ve talked to said the same things with their international deliveries. Perhaps there is some sort of rules saying someone needs to sign for stuff coming from out of the country. I won’t be here because they’ve quoted around 10am as their delivery time guarantee. I’ll have to sign for it and leave the “door hanger/sticky” for Monday I guess unless I can pick it up after work at the airport when I get the sticky at lunch time when I’m home.