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Is it possible to read flash memory of microcomputer?

Latest Updated:11/10/2008

Question:

[Flash Development Toolkit V.2, V.3 and V.4 ] Is it possible to read flash memory of microcomputer?

Answer:

Yes. However, the conditions that apply to reading data differ according to the MCU family.

(1)SuperH RISC engine Family:
If the MCU power is not turned OFF after the program is written, use the following process to read the programmed values.
In the Flash Development Toolkit Menu: select [Device] → [Upload] to open the Upload dialog box. Enter the address range, data length and other information requested in the dialog box, and then click the [Upload] button. The data read will be displayed in the editor window.On the other hand, if the power to the MCU has been turned off after the program was written, the data can only be read based on the MCU startup mode.

(a) When starting up the MCU in the Boot Mode: in this case, the MCU has already erased all data in the flash memory. This is due to the specifications of the MCU boot program embedded in the MCU, not due to the specs of the Flash Development Toolkit. In other words, even if you use a programmer other than the Flash Development Toolkit, the flash memory will still be completely erased. The data read out will be in the erased state, or "FF."
This specification is embedded in the MCU to make sure a third party cannot read the contents of the flash memory for malicious reasons.

(b)When starting up the MCU in the User Programming Mode: The data in the flash memory is not erased and can be read at any time.

(2)H8SX Family:
Same as (1) above.

(3)>H8S Family:
Same as (1) above.

(4)H8 Family:
Same as (1) above.

(5)M16C Family (M32C, M16C, M16C/Tiny), R8C Family and 740 Family Flash memory products:
The programmed values can be read with the following process.
In the Flash Development Toolkit Menu: select [Device] → [Upload] to open the Upload dialog box. Enter the address range, data length and other information requested in the dialog box, and then click the [Upload] button. The data read will be displayed in the editor window.
However, M16C Family products have an ID code that is used as a protect function. Therefore, the data can only be read if the ID code entered in the ID Code Dialog and the ID code programmed in the MCU are the same.
When the ID code programmed in the MCU is the initialization value (H'FF FF FF FF FF FF FF or H'00 00 00 00 00 00 00), The Flash Development Toolkit automatically verifies the codes and the ID Code Dialog is not displayed.
After the ID code is entered, verification is done automatically until power to the MCU is turned OFF or the device is disconnected. Therefore, the ID Code Dialog box is never displayed.

(6)740 Family QzROM Version:
A value written using the following procedure can be read.
In the Flash Development Toolkit Menu: select [Device] → [Upload] to open the Upload dialog box. Enter the address range, data length and other information requested in the dialog box, and then click the [Upload] button. The data will be displayed in the editor window.
However, the QzROM embeds a protect function. If this function is enabled, the data cannot be read.

Suitable Products
Flash Development Toolkit