Writing Data, Specifying Addresses | Fujitsu F202RA, MB89202

CHAPTER 17 FLASH MEMORY

17.5.2Writing Data

This section describes the procedure for issuing the Write command to write data to the flash memory. Figure 17.5-1shows an example of the flash memory write procedure.

■Writing Data

The data write automatic algorithm of the flash memory can be started by sending the Write command in the command sequence table (see Table 17.3-1in Section "17.3 Starting the Flash Memory Automatic Algorithm ") continuously to the flash memory. When data write to the target address is completed in the fourth cycle, the automatic algorithm and automatic write are started.

■Specifying Addresses

Writing can be done in any order of addresses. However, the Write command writes only data of one byte for each execution.

■Notes on Writing Data

Writing cannot return data 0 to data 1. When data 1 is written to data 0, the data polling algorithm (DQ7) or toggle operation (DQ6) does not terminate and the flash memory elements are determined to be faulty. If the time prescribed for writing is thus exceeded, the timing limit exceeded flag (DQ5) is determined to be an error. Otherwise, the data is viewed as if dummy data 1 had been written. However, when data is read in the read/reset state, the data remains 0. Data 0 can be set to data 1 only by erase operations.

All commands are ignored during execution of the automatic write algorithm. If a hardware reset is started during writing, the data of the written addresses will be unpredictable.

■Writing to the Flash Memory

Figure 17.5-1is an example of the procedure for writing to the flash memory. The hardware sequence flags (see Section "17.4 Confirming the Automatic Algorithm Execution State ") can be used to determine the state of the automatic algorithm in the flash memory. Here, the data polling flag (DQ7) is used to confirm that writing has terminated.

The data read to check the flag is read from the address written to last.

The data polling flag (DQ7) changes at the same time that the timing limit exceeded flag (DQ5) changes. For example, even if the timing limit exceeded flag (DQ5) is "1", the data polling flag bit (DQ7) must be rechecked.

Also for the toggle bit flag (DQ6), the toggle operation stops at the same time that the timing limit exceeded flag bit (DQ5) changes to "1". The toggle bit flag (DQ6) must therefore be rechecked.

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F202RA, MB89202 specifications

The Fujitsu MB89202 and F202RA microcontrollers are part of the 16-bit microcontroller family, renowned for their robust performance and versatility in a variety of embedded system applications. These devices are tailored for high-efficiency operation across diverse industries, including automotive, consumer electronics, and industrial automation.

One of the main features of the MB89202 is its powerful CPU core, which operates at a clock speed of up to 20 MHz. This enables the microcontroller to perform complex calculations and consumer-grade applications seamlessly. The architecture is designed to handle multiple tasks effectively, making it suitable for real-time operations.

Memory capacity is a vital characteristic of the MB89202, featuring on-chip RAM and ROM configurations. The microcontroller can accommodate different memory variants, providing developers with flexibility in memory allocation based on their application requirements. This adaptability facilitates applications ranging from simple control systems to complex data processing tasks.

The F202RA variant extends the capabilities of the MB89202 by integrating advanced peripheral functions. It includes built-in timers, A/D converters, and serial communication interfaces, which are essential for interfacing with other hardware components or sensors. The availability of these peripherals reduces the need for additional external circuits, thus contributing to a more compact and cost-effective design.

In terms of power management, the MB89202 series employs advanced power-saving technologies. The microcontroller offers various low-power modes, enabling devices to conserve energy during idle times, making it highly suitable for battery-operated applications. This characteristic not only enhances the efficiency of devices but also extends their operational lifespan.

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In summary, the Fujitsu MB89202 and F202RA microcontrollers stand out with their efficient performance, extensive memory options, integrated peripherals, and power-saving capabilities, making them ideal for a wide array of embedded applications. Their reliability and robustness further enhance their attractiveness for designers seeking advanced microcontroller solutions.

Fujitsu F202RA, MB89202 manual Writing Data, Specifying Addresses, Writing to the Flash Memory

Models: F202RA MB89202