Chapter 6

ColdFire Flash Module (CFM)

The MCF5282 incorporates SuperFlash® technology licensed from SST. The ColdFire Flash Module (CFM) is constructed with eight banks of 32K x 16-bit Flash to generate a 512-Kbyte, 32-bit wide electrically erasable and programmable read-only memory array. The CFM is ideal for program and data storage for single-chip applications and allows for field reprogramming without external high-voltage sources.

The voltage required to program and erase the Flash is generated internally by on-chip charge pumps. Program and erase operations are performed under CPU control through a command-driven interface to an internal state machine. All Flash physical blocks can be programmed or erased at the same time; however, it is not possible to read from a Flash physical block while the same block is being programmed or erased. The array used in the MCF5282 makes it possible to program or erase one pair of Flash physical blocks under the control of software routines executing out of another pair.

NOTE

The MCF5281 implements only 256 Kbytes of Flash; half that of the MCF5282.

6.1Features

Features of the CFM include:

512-Kbytes of Flash memory on the MCF5282 and 256-Kbytes of Flash memory on the MCF5281

Basic Flash access time of 2 clock cycles. Optimized processor Flash interface reduces basic Flash access time through interleaving and speculative reads.

Automated program and erase operation

Concurrent verify, program, and erase of all array blocks

Read-while-write capability

Optional interrupt on command completion

Flexible scheme for protection against accidental program or erase operations

Access restriction controls for both supervisor/user and data/program space operations

MOTOROLA

Chapter 6. ColdFire Flash Module (CFM)

6-1

Page 143
Image 143
Motorola MCF5281, MCF5282 user manual Chapter ColdFire Flash Module CFM, Features