Basics

Memory modules using either the EEPROM or FLASH technology can be re-programmed or deleted (erased) with the Galep-4 simply by selecting the proper method in software. No special deleting device is required (cf. EPROM technology).

Because of their properties these devices can be used for programming in the target system.

EEPROM Technology

This type of device allows for a selective change of individual memory cells. As every read-access is followed by an internal programming procedure, this device is basically slower than the FLASH devices as far as read-access time is concerned.

FLASH Technology

The FLASH technology requires that memory cells be deleted before being re-programmed. Usually the memory cells are comprised into sectors, which in turn may be deleted selectively.

Pseudo- EPROMs

Pseudo EPROMs are memory modules using FLASH technology. Terminal assignment here is such as to allow for the modules to be built into systems designed for EPROMs. As these modules can be deleted very quickly using a programming device, they may be more suitable than EPROMs in an environment where content is subject to frequent and constant change.

Write Protection Mechanisms

Modern devices offer a variety of ways to switch logic, which offers protection against the involuntary loss of data. Further, however, these devices can now also offer the possibility to enhance the level of write protection, by programming certain memory cells (Software Protection) and by permanently protecting certain memory blocks from being programmed (Sector Protection, Boot-block Lockout).

To activate Software Protection: Before programming, open the Options dialog box, and highlight Software Protection.

When programming a device with Software Protection enabled, that protection is being permanently enabled, regardless of the device's previous setting. Please note that you can re-program a device with Software Protection enabled only after deactivating that software protection first. Software Protection can usually only be deactivated by erasing the device.

To activate Sector Protection and Boot Block Lockout respectively, before programming, open the Options dialog box and highlight the appropriate entry. Keep in mind that activating this protection mechanism is often considered an OTP procedure, and cannot be reversed, even with the programming device.

For more detailed information concerning protection mechanisms and their functions please refer to the data sheet for that module.