Command interface
M58LT256JST, M58LT256JSB
4.10.2
Program and verify phase
The program and verify phase requires 32 cycles to program the 32 words to the write
buffer. The data is stored sequentially, starting at the first address of the write buffer, until the
write buffer is full (32 words). To program less than 32 words, the remaining words should be
programmed with FFFFh.
Three successive steps are required to issue and execute the program and verify phase of
the command.
1. Use one bus write operation to latch the start address and the first word to be
programmed. The Status Register Bank Write status bit SR0 should be read to check
that the P/EC is ready for the next word.
2. Each subsequent word to be programmed is latched with a new bus write operation.
The address must remain the start address as the P/EC increments the address
location.If any address is given that is not in the same block as the start address, the
program and verify phase terminates. Status Register bit SR0 should be read between
each bus write cycle to check that the P/EC is ready for the next word.
3. Once the write buffer is full, the data is programmed sequentially to the memory array.
After the program operation the device automatically verifies the data and reprograms if
necessary.
The program and verify phase can be repeated, without re-issuing the command, to
program additional 32 word locations as long as the address remains in the same block.
4. Finally, after all words, or the entire block have been programmed, write one bus write
operation to any address outside the block containing the start address, to terminate
program and verify phase.
Status Register bit SR0 must be checked to determine whether the program operation is
finished. The Status Register may be checked for errors at any time but it must be checked
after the entire block has been programmed.
4.10.3
Exit phase
Status Register P/EC bit SR7 set to ‘1’ indicates that the device has exited the buffer
enhanced factory program operation and returned to read Status Register mode. A full
Status Register check should be done to ensure that the block has been successfully
programmed. See Section 5: Status Register for more details.
For optimum performance the Buffer Enhanced Factory Program command should be
limited to a maximum of 100 program/erase cycles per block. If this limit is exceeded the
internal algorithm continues to work properly but some degradation in performance is
possible. Typical program times are given in Table 16.
See Appendix C, Figure 27: Buffer enhanced factory program flowchart and pseudocode for
a suggested flowchart on using the Buffer Enhanced Factory Program command.
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