PCMCIA Memory Issues

PC CARD / PCMCIA Laptop Memory

Card and Socket Services

PC-Card and Socket Services consists of a set of device drivers that are loaded in the CONFIG.SYS file. These drivers provide an interface that allows most PCMCIA cards to be recognized automatically when inserted into any of the PCMCIA slot. It provides ease of configuration and installation of new cards. The advantage of this interface allows PC-Cards to be "Hot-Swapped" (removed while the system is running) and exchanged with other PCMCIA cards. Card and Socket Services allows a multitude of different PCMCIA hardware to be accessed in the active work session, without having to reset or turn off the computer.

The down side to Card and Socket services is the impact on DOS memory. Approximately 45K-120K of conventional DOS memory is consumed to provide this interface. An additional 64K of upper memory is also reserved to access and manage PCMCIA resources. The direct memory impact to both and DOS and Windows ranges from 109K-184K or more, before anything else is loaded. To complicate the problem further, the reserved memory space fragments the upper memory region into small, somewhat unusable memory blocks. Not recovering this wasted memory generally leaves the system lacking enough available memory to run critical applications.

Recover enough memory to run applications that run fine on a desktop.

In many cases the user either has a Modem, Network card, or both. In these cases, most of the reserved upper memory can be recovered through a simple procedure. During this procedure, not only do you recover valuable memory, but in the same process, memory can also be re-mapped to defragment the upper memory area.

In the modem only environment, only 4K-8K of upper memory needs to be reserved. In the modem/network environment, only 4K-24K must be reserved. That means that 40K-60K of the 64K reserved upper memory block goes unused and wasted.

ATLast! has a PCMCIA interface that detects and protects the actual upper memory required and recovers the unused space. In addition, ATLast! recovers any other upper memory not previously configured. This typically results in an additional 32K-100K upper memory space. Once configured, the automatic memory recovery and automated maintenance features of ATLast! increase user productivity and greatly reduce problems requiring technical support.

Point Enablers

An alternative to PC-Card and Socket Services is to use a Point Enabler software package which allows the PCMCIA card to be accessed directly. Using a Point Enabler instead of Card and Socket services provides a major reduction of memory impact. Many PCMCIA cards ship with such an enabler program on their installation disk. Others may be downloaded from the manufacturers BBS or Internet web site.

Although Enabler programs do not provide the ease of installation of Card and Socket services, once configured, require little or no memory to initialize the specific PCMCIA PC-Card. Generally, either one or two enabler programs can be run at the same time. The only down side of using Point Enablers is that they are more difficult to configure and the "Hot-Swapping" features are not available.

If you need the extra memory, it will be well worth the time to configure a Point Enabler.

ATLast! gets expensive laptops working and keeps them working!

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