16.1 Description

This Static Memory Controller (SMC) is capable of handling several types of external memory and peripheral devices, such as SRAM, PSRAM, PROM, EPROM, EEPROM, LCD Module, NOR Flash and NAND Flash.

The SMC generates the signals that control the access to external memory devices or peripheral devices. It has 4 Chip Selects and a 26-bit address bus. The 16-bit data bus can be configured to interface with 8- or 16-bit external devices. Separate read and write control signals allow for direct memory and peripheral interfacing. Read and write signal waveforms are fully configurable.

The SMC can manage wait requests from external devices to extend the current access. The SMC is provided with an automatic Slow Clock mode. In Slow Clock mode, it switches from user-programmed waveforms to slow-rate specific waveforms on read and write signals.

The SMC embeds a NAND Flash Controller (NFC). The NFC can handle automatic transfers, sending the commands and address cycles to the NAND Flash and transferring the contents of the page (for read and write) to the NFC SRAM. It minimizes the CPU overhead.

The SMC embeds a programmable binary BCH encoder/decoder that generates redundancy information at encoding for both SLC and MLC NAND devices. It supports redundancy for correction of 2, 4, 8, 12, 24, or 32 errors per sector of 512 or 1024 bytes.

The External Data Bus can be scrambled/unscrambled by means of user keys.