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Programmable Hardware Manual (PHM)
© Tibbo Technology Inc.
Note that the circuit above shows an RJ45 jack with two LEDs. Further information
on the use of these LEDs can be found in the
4.4.1.3
Flash and EEPROM Memory
The EM510 has 512KBytes of internal flash memory and 2048 bytes of EEPROM
memory (see
Specifications and Ordering Info
).
A portion of the internal flash memory is used to store the TiOS firmware. When you
are performing a firmware upgrade it is this memory you are saving the firmware
binary into.
The rest of this flash memory is available to your Tibbo BASIC/C application. The
internal flash memory
cannot
be used as a flash disk. On the E510, the fd. object
(see TIDE, TiOS, Tibbo BASIC, and Tibbo C Manual) requires an external flash IC.
As shown on the schematic diagram below, this flash IC is ATMEL AT45DB041. When
connected, this flash IC is used exclusively by the flash disk (fd.) object and
provides 1MB of storage. When the flash disk (fd.) object is enabled, GPIO1, GPIO3,
and GPIO4 are automatically handled by TiOS and your application should not
attempt to manipulate these lines at the same time. The fd. object is enabled in the
Project Settings dialog of Tibbo IDE software. To enable, click on the Customize
button (of the Project Settings dialog) and set "Flash disk (fd.) object" to "Enabled."
The EEPROM is almost fully available to your application, save for a small 32-byte
area called "special configuration area". The EEPROM is accessed through the stor.
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 EM510 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