EFM32WG Datasheet, PDF (188/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

14.3.14 NAND Flash Support
...the world's most energy friendly microcontrollers
NAND Flash devices offer high density at relatively low cost when compared to NOR Flash devices.
Unlike NOR Flash, which offers random read access, NAND Flash devices are based on page access
and use an indirect interface. Furthermore, a NAND Flash can contain invalid bits leading to invalid
blocks, which leads to requirements such as bit error detection/correction and bad block management.
The EBI offers support for glueless connection of a NAND Flash by implementing dedicated
EBI_NANDREn and EBI_NANDWEn pins and by providing hardware for single error correction
double error detection (SEC-DED) Error Correction Code (ECC) generation. NAND Flash support is
enabled by setting the EN bitfield in the EBI_NANDCTRL register to 1. The BANKSEL bitfield in
EBI_NANDCTRL defines which memory bank has a NAND Flash devices attached to it. NAND Flash
data width, read timing, and write timing are programmed via the standard EBI registers as described in
Section 14.3.14.2 (p. 189) . ECC support is described in Section 14.3.15 (p. 193) .
Both standard and Chip Enable Don't Care (CEDC) NAND Flash devices are supported and they can
be attached as shown in Figure 14.25 (p. 188) and Figure 14.26 (p. 189) respectively. For standard
NAND Flash devices, the Chip Enable (CEn) pin needs to remain asserted low during the entire read
cycle busy period, in which data is transferred from the memory array into the NAND Flash internal
data registers in order to prevent an early return to standby mode. CEDC NAND Flash devices do not
have this restriction, but they do not support the automatic sequential read function. For CEDC NAND
Flash the shared EBI_REn and EBI_WEn pins can be used instead of the dedicated EBI_NANDREn
and EBI_NANDWEn pins.
Figure 14.25. EBI Connection with Standard NAND Flash
EBI
( EFM3 2 )
GPIO ⁽⁰⁾
EBI_A[ 25] ⁽¹⁾
EBI_A[ 24] ⁽¹⁾
EBI_NANDREn
EBI_NANDWEn
EBI_AD[ ] ⁽³⁾
GPIO
GPIO ⁽⁴⁾
CEn
ALE
CLE
REn
WEn
NAND
Flash
IO[ ]
WPn
R/B
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
188
www.energymicro.com