TYAN TOMCAT I7221 User Manual page 49

Tomcat i7221 S5150
Onboard FDC Controller
Select Enabled if your system has a floppy disk controller (FDC) installed on the system board
and you wish to use it. If you install an add-in FDC or the system has no floppy drive, selec t
"Disabled" in the field.
Enabled / Disabled
Onboard Serial Port 1
Select an address and corresponding interrupt for the first serial port.
3F8/IRQ4 / 2F8/IRQ3 / 3E8/IRQ4 / 2E8/IRQ3 / Auto
Onboard Serial Port 2
Select an address and corresponding interrupt for the second serial port.
3F8/IRQ4 / 2F8/IRQ3 / 3E8/IRQ4 / 2E8/IRQ3 / Auto
Onboard Parallel Port
To use the parallel port on the system, select an address and corresponding interrupt for the
parallel port.
378/IRQ7 / 278/IRQ5 / 3BC/IRQ7 / Disabled
Parallel Port Mode
This field allows the user to select the parallel port mode. The default value is Standard that
automatically selects the correct mode to use. The other modes are explained as follows:
SPP works with all parallel port devices. How ever, it is the slowest transfer mode and should
only be used when faster transfer modes cannot be used.
There are two faster bidirectional modes available - the ECP (Extended Capabilities Port) and
EPP (Enhanced Parallel Port) modes.
ECP uses the DMA protocol to achieve data transfer rates of up to 2.5Mbytes/s and provides
symmetric bidirectional communication. On the other hand, EPP uses existing parallel port
signals to provide asymmetric bidirectional communication.
Generally, because of its FIFOs and the DMA channel it uses, ECP is good for large data
transfers (useful for scanners and printers). On the other hand, EPP is better with links that
switch di r ections frequently (like parallel port drives).
There are two versions of the EPP transfer protocol - EPP1.7 and EPP1.9. Generally, EPP1.9
is the preferred setting because it supports the newer EPP1.9 devices and most EPP1.7
devices; and offers advantages like support for longer cables. However, because certain
EPP1.7 devices cannot work properly with an EPP1.9 port, this BIOS feature was
implemented to allow you to set the EPP mode to EPP1.7 when such an issue occurs.
Therefore, it is recommended that you set this BIOS feature to EPP1.9. But if you have trouble
connecting to your parallel port device, switch to EPP1.7.
However, the manufacturer of your parallel port peripheral may have designated a preferred
parallel port mode for the device in question. In that case, it's best to follow their
recommendation.
For those who don't know what mode to select but at least know that their parallel port device
supports bidirectional transfers, the BIOS offers the ECP+EPP mode. If you select this mode,
then the parallel port device will be able to use either one of those modes. However, this
should be considered as a last resort as you may be needlessly tying up an IRQ for nothing if
your device does not use ECP at all. Or, the BIOS may not select the best parallel port mode
for the device. If possible, set the parallel port to the transfer mode that best suits your parallel
port device.
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Chapter 3: BIOS Setup