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Programmable Hardware Manual (PHM)
© Tibbo Technology Inc.
object (see TIDE, TiOS, Tibbo BASIC, and Tibbo C Manual). Details on the special
configuration area are provided in the Platform-dependent Programming Information
section inside the EM1206 platform documentation (same manual).
On the advice of one of our customers we are giving you the following
reminder: Like all other EEPROMs on the market, EEPROM ICs used in Tibbo
devices allow for a limited number of write cycles. As the Wikipedia article on
EEPROMs (
https://en.wikipedia.org/wiki/EEPROM
) states, the EEPROM "
...has a
limited life for erasing and reprogramming, now reaching a million operations in
modern EEPROMs. In an EEPROM that is frequently reprogrammed while the
computer is in use, the life of the EEPROM is an important design consideration.
"
When planning to use the stor. object, please carefully consider if the planned mode
of EEPROM use will allow the EEPROM to work reliably through the entire projected
life of your product. For more information see
Prolonging and Estimating EEPROM
Like all other flash memory devices on the market, flash ICs used in Tibbo products
only allow for a limited number of write cycles. As the Wikipedia article on flash
memory (
https://en.wikipedia.org/wiki/Flash_memory
) explains, modern flash ICs still
suffer from comparatively low write endurance. In Tibbo devices, this endurance is
around 100'000 write cycles per sector. When you are using the flash memory for
file storage, the fd. object employs sector wear leveling to maximize the life of the
flash IC (but the life still remains limited). If your application employs direct sector
access, then it is your job to plan the application around the life limitations of the
flash memory. For data that changes often, consider using the EEPROM memory
instead. EEPROMs have much better endurance.
4.3.1.6
Real-time Counter
The real-time counter (RTC) of the EM1206 is a free-running 40-bit register that
increments at a rate of 128Hz.
As a source of backup power, the EM1206 can rely on a supercapacitor. Suggested
schematic diagram is shown below. The resistor is used for current limiting: a fully
discharged supercapacitor creates a nearly short-circuit current inrush when it
starts charging and this can damage the power supply of your host board.
The supercapacitor has many advantages- it charges almost instantly and has
virtually unlimited lifespan. The disadvantage is that the supercapacitor is only able