oNormal Behavior: The value will be used to configure the 82557 at initialization time. Setting it to a low value will force frequent internal arbitration, which will affect overall performance. The value can be tuned to obtain optimum balance between the TX and Rx DMA machines.
oPossible Errors:
If the RXDMACOUNT parameter is set to an invalid value, the parameter is ignored and the default value is used, and a message indicates a "Parameter value out of range" error.
•TXDMACOUNT
oSyntax: TXDMACOUNT=[0..127 0x0..0x7F]
oExample: TXDMACOUNT=16
oDefault: 0 implying that the Tx DMA will continue until it is done. No other DMA request can preempt it.
oNormal Behavior: The value will be used to configure the 82557 at initialization time. Setting it to a low value will force frequent internal arbitration, which will affect overall performance. The value can be tuned to obtain optimum balance between the Tx and Rx DMA machines.
oPossible Errors:
If the TXDMACOUNT parameter is set to an invalid value, the parameter is ignored and the default value is used, and a message is indicates a "Parameter value out of range" error.
•TRANSMITBUFFERS
oSyntax: TRANSMITBUFFERS=[4 .. 30]
oExample: TRANSMITBUFFERS=14
oDefault: 4 for DOS driver, 10 for OS/2 driver
oNormal Behavior: The driver allocates the number of buffers indicated by the parameter value.
oPossible Errors:
If the value provided is out of range, the parameter is ignored and the default value is used, and a message indicates a "Parameter value out of range" error.
CAUTION: If the number of buffers allocated causes the driver’s size to exceed MAXIMUM, the driver adjusts the number of buffers downward, by reducing each of the counts of transmit/receive buffers by one until the total allocation will fit in the available memory. A message indicates the actual number of buffers allocated. Under DOS without Window for Workgroups (WFW), MAXIMUM is defined as 64Kb for all code and data.
Under DOS and WFW, the driver must not claim more space than its load size, but since the driver cannot detect that it is running under WFW, a message warns the user when the size allocated exceeds the size of the driver when loaded. Under OS/2, MAXIMUM is defined as 64Kb for all data.
•RECEIVEBUFFERS
o Syntax: RECEIVEBUFFERS=[4 .. 30]
o Example: RECEIVEBUFFERS=14
o Default: 8 for DOS driver, 10 for OS/2 driver
o Normal Behavior: The driver allocates the number of buffers indicated by the parameter value.
oPossible Errors:
If the value provided is out of range, the parameter is ignored, the default value is used, and a message indicates a "Parameter value out of range" error.
Adapter configurations 85