M35B32 datasheet(12/44 Pages) STMICROELECTRONICS

12 / 44 page

Operating features

M35B32

12/44

DocID18391 Rev 4

Operating features

4.1

An easy way to modify data

The Page Write (PW) instruction provides a convenient way of modifying data (1 up to 256

contiguous bytes at a time), and simply requires the start address, and the new data in the

instruction sequence.

4.2

A fast way to store data

The Page Program (PP) instruction provides a fast way of modifying the data (1 up to 256

contiguous bytes at a time) in the Event sector, provided that these data bytes were erased

(by the completion of an earlier Page Erase instruction).

When addressing the Event sector (Sector 0, see Figure 5), the Page Program instruction is

executed in a very short time (tFP, see Table 11), that is about 5 times faster than when

executing a Page Program (or Page Write) instruction in the Data sector.

To be correctly used, the Event sector has to be first erased. When an event occurs, data

are programmed in the Event sector within a fast time. Later on, when the device receives

less requests from the application, the contents of the Event sector can be copied/written

into the Data sector (to benefit from the standard data retention time of 40 years), after what

the Event sector content can be erased (using only one instruction: the Sector Erase

instruction).

4.3

Polling during a write, program or erase cycle

A further improvement in the write, program or erase time can be achieved by not waiting for

the worst case delay (tPW, tPP, tPE, or tSE). The write in progress (WIP) bit is provided in the

Status Register so that the application program can monitor its value, polling it to establish

when the previous cycle is complete.

M35B32 Datasheet(PDF) 12 Page - STMicroelectronics