MMC2114 MOTOROLA [Motorola, Inc], MMC2114 Datasheet - Page 230

• Manufacturer Part Number: MMC2114
• Description: M CORE Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Second Generation FLASH for M•CORE (SGFM)
10.8 SGFM User Mode
10.8.1 Read Operations
10.8.2 Write Operations
Advance Information
230
Normal operation of the SGFM occurs in user mode. The SGFM
registers, subject to the restrictions previously noted, can generally be
read and written. Reads of the SGFM array generally occur normally and
writes behave according to the setting of the KEYACC bit in SGFMCR.
Program, erase, and verify operations are initiated by the CPU. Special
cases of user mode apply when the CPU is in low power or debug modes
and when the MCU boots in master mode or emulation mode.
A valid read operation occurs whenever a transfer request is initiated by
the M•CORE, the MLB address is equal to an address within the valid
range of the SGFM memory space, and the read/write control indicates
a read cycle. Aligned read accesses (byte, halfword, or word) complete
in one system clock cycle. Misaligned accesses are not allowed and
result in a cycle termination transfer error.
In order to reduce power at low system clock frequencies, the sense
amplifier timeout (SATO) block minimizes the time during which the
sense amplifiers are enabled for read operations. The sense amplifier
enable signals to the FLASH timeout after approximately 50 ns.
A valid write operation occurs whenever a transfer request is initiated by
the M•CORE, the MLB address is equal to an address within the valid
range of the SGFM memory space, and the read/write control indicates
a write cycle.
The action taken on a valid SGFM array write depends on the
subsequent user command issued as part of a valid command
sequence. Only aligned 32-bit write operations are allowed to the SGFM
array. Byte and halfword write operations will result in a cycle termination
transfer error.
Freescale Semiconductor, Inc.
Second Generation FLASH for M•CORE (SGFM)
For More Information On This Product,
Go to: www.freescale.com
MMC2114 • MMC2113 • MMC2112 — Rev. 1.0
MOTOROLA