I am using the DS1643 which contain both non voliate ram and a RTC. also, in my project, i use the timer 1 interrupt to counter the machine operation time: unsigned char second, min, hour; i use XBYTE[0x1ffe0]=second; XBYTE[0x1ffe1]=min; XBYTE[0x1ffe2]=hour; then i have a function to recall the NVram data to the counter variavle. it is not problem for the reset the system, and all data can be keep. however, when i remove the power supply, all data are going wrong. How can i solve this problem? any programming skills needed for using NVRAM? Pls help!!!!!!!!!!!!!!!! many thx!!!!!!!!!!!!!!
Hi Guy, there no such think called Non Volatile RAM during power off mode. In RAM, only first few location will be clear and others not clear, So we can use that area to keep some variable for cold start. But in warm start:If you really want to keep your data even during power off mode then you must use EEPROM.
You don't seem to know what the original poster is talking about. That chip is, for all means and purposes, nonvolatile RAM. More precisely it's battery-backed RAM, just like kind used to store configuration data in PCs.