An UPSAC boot card must be 512KB or larger. These cards are used for software upgrades and diagnostics. The boot card does not use a standard PC format. Data cards, used only for storing configurations and bitmaps, may be any size so long as there is 20 percent headroom above the total configuration and bitmap size for directory and other information.
When possible, (if you don't have to format them in a laptop to get it to recognize the card) data cards should be formatted in the UPSAC processor, not the PC. Different format utilities come up with some irregular formats which may not be compatible with Unison.
Windows NT/2000/XP® Concerns
On the majority of Windows NT/2000/XP computers, the PCMCIA reader drivers seem to require that cards have "attribute". Cards with or without attribute will likely work with the UPSAC, but you'll need attribute in order to access the configuration file from a pc.
Windows 95/98® Concerns
If you haven't used your laptop before with SRAM cards, type "SRAM" into Windows 95/98 Help. View the topic entitled "To install PC Card support for an SRAM memory PC Card". Add the appropriate lines to your "config.sys" file as described in the Windows Help file.
For some reason many computers will refuse to recognize SRAM cards as readable media.
The solution is:
Insert the card (a blank card is preferred)
Go to a DOS prompt
Choose a currently unassigned drive letter (E works for a lot of Laptops)
At the DOS prompt, format that drive.
This may fail up to 3 times and then the computer will recognize the SRAM card as valid media storage and Map the drive.
You can then exit DOS and access the card normally.
Centennial Technologies 512K PCMCIA SRAM Recharge Card (ETC P/N: Z594) uses a pair of lithium ion rechargeable batteries for data retention. Four to six hours in a host device constitutes a full charge which is specified to last for 9 months. Centennial, however, recommends recharging the card for at least four hours every six months. Because lithium ion rechargeables are used rather than nickel cadmium, there is no need to completely drain the batteries before starting a new charge cycle.
Type I PCMCIA SRAM Recharge Card 5 Volt 512K (My guess is that the memory controller on the UPSAC cannot address cards larger than 512K) Note: Type II and III cards will not fit in the CEM PCMCIA slot. Flash memory cards will also not work, as the UPSAC hardware does not support flash cards. Some brands do not work with the UPSAC or our software. Compatible cards have EPROMS in them that are compatible with our hardware. Finding them is unfortunately a hit and miss process. The most compatible cards we have found are the Centennial Technologies 512K 5V SRAM Recharge Cards. (Model numbers: SL512-15-10191-01 33396 254 and SR512-15-11191-01 PM31004 12498 314)