The IBM Turbo 16/4 Token-Ring PC Card 2 (referred to as PC Card) is a credit-card-sized adapter that provides an interface between computers and Token-Ring networks. It is part of the shared RAM family of adapters. The PC Card is designed for computers with slots that comply with the standards for the Personal Computer Memory Card International Association (PCMCIA) Release 2.1, Type II slots.
Features include:
The Auto Ring Speed function avoids problems due to manual configuration of an incorrect data rate. The function also eliminates the need to reconfigure the PC Card if the data rate of the ring is changed.
You should not select Auto Ring Speed if you might be the first one to attach to your ring. The PC Card will not allow you to connect in this case. You will have to try to connect again after another Token-Ring user is on the ring.
When using the PC Card in Auto Ring Speed mode, it is important to be aware of transmit buffer limitations that may cause problems. A 16-Mbps Token Ring can support transmit buffer sizes up to 17 960 bytes. A 4-Mbps Token Ring can support transmit buffer sizes up to 4464 bytes. This is a restriction due to the speed of the media. This might affect your application.
If your software is configured to try 16-Mbps ring operation first and you plan to utilize Auto Ring Speed, use a transmit buffer size less than or equal to 4464 bytes. This will ensure that you will not have any open PC Card errors due to improper transmit buffer size if your PC Card must change ring speed.
The device drivers for Turbo 16/4 Token-Ring PC Card 2 are fully backward-compatible with all of the previous versions of IBM Token-Ring Credit Cards, however there have been improvements in the hardware with the introduction of the Turbo PC Cards. That new hardware feature is referred to as Stealth Mode and can be used in the Turbo 16/4 Token-Ring PC Card 2 to remove power from the card by removing only the cable. The operating system will not sense the presence of the card in the slot with the cable detached.
With previous IBM Token-Ring Credit Cards, with the exception of the IBM Turbo 16/4 Token-Ring PC Card, the card and cable had to be removed from the computer to remove power to the slot and the detection of the adapter from the operating system.
When removing the cable from the PC Card while the system is running or connected to the network or both, stop the PC Card before you remove the cable or card, just as you normally would when removing any adapter from the system.
| Note: | If the cable is disconnected at boot time under a Plug and Play operating system, the operating system will not be aware of the PC Card's presence and will not try to load the device drivers for the PC Card. However, under an operating system which is not Plug and Play compliant, the operating system will try to load the PC card device drivers anyway and as a result the operating system will generate an error message referring to the adapter or the device drivers or both. |