Texas Instruments TMS320F20x/F24x DSP manual Preliminary

How the Algorithms Fit Into the Program-Erase-Reprogram Flow

PRELIMINARY

3.1 How the Algorithms Fit Into the Program-Erase-Reprogram Flow

The algorithms discussed in this chapter can be used to reprogram the 'F20x/F24x flash module multiple times. The clear algorithm, erase algorithm, and flash-write algorithm are used to prepare the flash memory for program- ming, while the programming algorithm is used to write a desired pattern of 0s to the array (program the array).

The programming algorithm and the clear algorithm are both implementations of the program operation. The difference between the two is the data that is written: the programming algorithm programs the user data, while the clear al- gorithm uses all 0s. All of the algorithms can be viewed as portions of a single flow diagram, as shown in Figure 3±1.

Note that in the algorithm flowcharts, the variable X represents the number of attempts at depletion recovery using the flash-write algorithm. It has been shown that if flash-write is not successful in depletion recovery after ten at- tempts, depletion recovery is not possible, and a device failure has occurred. Therefore, if ten flash-write attempts at depletion recovery are not successful, the algorithm returns a device failure error message.

3-2 PRELIMINARY