If you load the IBM LAN Support Program (LSP) drivers for the IBM
Token Ring adapter into upper memory blocks (UMB) using DEVICEHIGH
with MS-DOS, you may receive the following error message:
Invalid shared RAM address
To work around this problem, load the LSP drivers into low memory, or
load the drivers high, adding a comma (,) to the end of the DEVICEHIGH
line in the CONFIG.SYS file as follows:
IBM LAN Support Program (LSP) is essentially the IBM network adapter
software. Typically, there are three files loaded in the CONFIG.SYS
file for these drivers, each providing various levels of driver
support, much PROTMAN, NDIS driver, and 802.2 support in Microsoft LAN
The following shows the syntax for the IBM LSP drivers:
device=DXMCnMOD.SYS addr0, mem0, etr0, addr1, mem1, etr1
addr0 = Replace with locally administered MAC address for the
primary adapter or first.
mem0 = Replace with RAM location for the primary adapter or first.
See your IBM technical reference, Token Ring configuration
guide, or PS/2 reference disk to determine or change this
etr0 = Early token release functionality is provided if etr0=1 and
the data rate for adapter is greater than 4 megabits per
second; otherwise, this argument is ignored.
The file will be DXMC1MOD.SYS IBM 3270 for Workstation Program
support, or DXMC0MOD.SYS if Workstation Program support is not being