Hi Guys, I don't know if this question is to be asked here or no but anyway- Is there anybody who have used NV RAM of DS12887RTC. It turned out that 3 of my RTCs were working for some time properly and then their RAM content disappeared- I am doing some new code to store data on NV RAM and checking it with incoming data(through serial) So needed to remove my micro controller for few times to reprogram it However after a while RTC content used to disappear And even if I run my "First_Run"(to load RTC) I can't get that data on RTC. If anybody is experienced with NV RAM?RTC please help me. Thank you in advance
One more thing what I've found in my case- This is the 3rd chip I've damaged, In my program I've sent all the data from RAM to PC through serial (i.e. using hyperterminal) This one was working fine Till a moment - Once when I tried to switch off the circuit suddenly I got all the data(resetted i.e. every mem location was holding its own value) on serial and this is how I'm making them unrepairable. Second one was damaged in same way Now can anybody help me or can anybody explain whats happening? Thank you guys
Is there a sequence which should be followed while powering down like - 1. power down NVRAM then power down uC otherwise keep RAM always powered up just uC is powered down Thanks in advance
this is a valid question to ask: are you using a MAX232(equivalent) or one of those BLASTED so called "RS232 interfaces without the chip"
Erik
I'm using MAX232 obviously connected to Rx and Tx of uC but it shouldn't be problem right? As I'm reading from RAM and putting it on serial. Without chip serial communication doesn't happen with PC(sometimes)
I'm using MAX232 good Without chip serial communication doesn't happen with PC(sometimes) without WHICH chip?
Its MAX232 series IC like MAX232, HIN232, etc.
Can anybody suggest me proper circuit(proper way of Vcc/GND) to work with RTC because I'm working with breadboard and i think that would be the problem as every time i put 2-pin vcc/gnd in berg there used to be some weird data on hyperterminal
When I removed interrupt pin i.e. pin 19RTC -> pin3.2uC the program/circuit is working fine without any problem What should I do about it I want to use alarm interrupt One more thing when I'm reading RAM all the data is correct except alarm location is there any problem with reading alarm locations?
if you have ANY comminication with the PC with the MAX232 removed your circuit is DEAD WRONG.
you are in the wrong forum, this is Keil C, not hardware. try http://www.8052.com read the noobs guide and post your schematic.
Hello Erik I've seen that site and I'm a member but till now I couldn't find anything as forum keil is really awesome anyway i'll try it there no problem
www.8052.com/.../read.phtml
anybody has manual for weller iron?
Where you planning to reprogram the RTC in the Weller, or how do your question relate to this thread?
no i think the tit is broken and got to change it.
You you thought that the :beep: is broken, and decided that a thread named NV RAM was suitable for your question. But then, how where you planning on using any Keil tools/development boards to fix the broken :beep:?
Don't you think a Weller forum or a generic soldering forum or at least a generic electronics forum would be better suited for asking about the schematics of a Weller solder station? Besides, Weller have a good supply of spare parts, so you should not need any schematic unless something in the transformer/regulator box is fried.