The DR-Flash solution provides a simple software interface to use any flash device as a standard non-volatile, read/write, memory storage.
The OEM can customize the OEM layer (source code is provided) to various environments and types of hardware. Five sample files are provided to help you customize one for your target hardware.
Flash memory is similar to EEPROM except that it is faster to update, requires less power, is higher in density, as well as being more reliable and less expensive than EEPROM. Flash memory combines the advantages of ROM and RAM. Like ROM, it is non-volatile and is therefore suited to harsh environments. Many embedded systems exist in such environments where power interruptions, dust, extreme temperatures can cause rotating media to fail. Like RAM, flash memory can be written with new data. It also uses very low power requirements which makes it ideal for mobile products.
If you are embedding software such as DR-WebSpyder (Caldera's Web browser) you can upgrade the device with newer software versions by installing newer software onto the flash device. Once the flash disk is set up, system integrators can use it as a normal hard disk or floppy disk in which to install the necessary software.
Flash memory can be written to in bits but must be erased in blocks. These blocks range from 4K to 128K and all bytes in the block must be erased. Flash devices also have a limited lifetime before they wear out (typically 100,000 write/erase cycles per block). The device levelling feature of DR-Flash reduces the wear on certain areas by checking to see which parts have not been written to as much and will write data to those areas. DR-Flash hides the complexity of this from the user and the operating system.
If DR-Flash does not meet your embedded requirements, please contact Caldera to find out about further options. If you are embedding only a few files such as a bootable version of DR-DOS, you can use our existing technology for embedding DR-DOS into ROM. This information is available in the Embedding DR-DOS in ROM Guide.
| DR-Flash File Descriptions | |
|---|---|
| Filename | Description |
| CDISK.OBJ | CDISK is the main utility for creating the flash disk. |
| CDISKM.OBJ | This is the message file for CDISK. These are in English. |
| DB.OBJ | This is the DR-DOS boot sector. |
| TARGET1-5.ASM | These are the sample source code files to show different hardware implementations. You can use the most suitable one to customize for your particular device. |
| MAKECD.BAT | This is the batch file used to build the CDISK.EXE utility. |
| IBMROS.EQU MSDOS.EQU RDISK.EQU | Include files. |