Hi Guys,
Now I think I'm a fairly logical bloke, but this one has me stumped.
I bought 4 of those DS1307 + 24C32 EEprom boards off the internet.
When they arrived and unpacked one out of the cellophane packets (yep you read it right)
Put a battery in the holder and connected it to an already working I2c setup with terminal.()
I ran the program that searches for I2C devices and they other devices that were connected to the bus came up but now there was an addition,
A0 EEprom, strange I thought, where's the D0 RTC.
Checked all the connections to the PCB and all the correct voltages were in the correct locations on the chip, which they were.
Loaded up the DS1307 software with the same result, no reply.
I tried a few other pieces of code from the net and the forum, still to no avail.
Since it came out of a cellophane packet, I thought, could be statically dead.
Proceeded to unpack another and connect it. Same result
Same for the third.
Thinking a bit, I deduced that the I2c connections to the board were correct, by the fact that the EEprom (A0) is detected, and, also measuring the tracks point to point were correct. Voltages were all correct (including the battery voltage)
Decided to get drastic and remove all components off of one board except the RTC chip, xtal, battery holder and resistor from the battery to the chip (which in latter tests I reduced in value to zero).
Still no comms with the RTC, EEprom found OK on every test.
I thought maybe, there was a crook batch of RTC chips on these boards, so I ordered a couple of DS1307 from RS Components, when they arrived, fitted one to the PCB and low and behold, still nothing.
Getting a little miffed now, I spend a damn good $4.00 on these 4 boards :)
Out with my Philips PCF8583 RTC chip which has identical pin outs except for pin three, in the PCF, it's not battery, but an address line to change the address of the chip.
Did a quick lashed up on a solder less breadboard, turned it on, and immediately, it started working. Ran the MS Electronics (1998) version
of software, and it did writes (and did changes) and reads correctly.
Now soldered a DS1307 onto a breakout PCB to get the .1 spin spacing, tested pin to pin connections for continuity and after removing the Pin3 A0 link to 0V, plugged in the DS1307 in place of the working PCF8583. Connected the battery to pin 3 of the DS chip, and stuff me, it still didn't work.
Some of you that know your chips are thinking yes the original PCF8583 address is A0 and so is the EEPRom (bad mistake by all those manufacturers, since the address was already taken by Phillps)
But As explained, On the PCB, The EErom had been removed from the PCB, and the lash up didn't have an EEprom connected.
Timing ?. I did slow the clock using the Config I2cdelay from 10 all different values to 255, nothing changed.
[b:8f85bfcbe7]So I guess the question is has anybody got any ideas about whats going on.[/b:8f85bfcbe7]
Oh yea, the other thing, can't see a 32K oscillation, but this could be turned off in the clock (bit). But it cant be turned on due to lack of I2c comms.
Thanks to all
Deanus
[b:8f85bfcbe7][color=red:8f85bfcbe7](BASCOM-AVR version : 2.0.7.6 )[/b:8f85bfcbe7][/color:8f85bfcbe7]
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