Q49285: Losing Data When Mouse and Data Transfer Are Involved

Article: Q49285
Product(s): See article
Version(s): 6.00 6.11 6.14 6.24 6.24b
Operating System(s): DOS
Keyword(s): ENDUSER | | mspl13_basic
Last Modified: 22-MAR-1990

Several customers report lost data or a system lock up when
transferring high speed data from a modem or mainframe through a
serial port. The mouse was resident in memory when the problem
occurred.

With communications going through COM2:, the interrupt 3 is in use.
This interrupt has a higher priority than either interrupt 4 (for a
mouse in COM1:) or interrupt 5 (bus mouse with interrupt 5 set on the
J4 jumper).

You should ensure that the communications equipment is loaded onto
COM2: so that it can take advantage of the higher priority interrupt.
The phenomenon is inherent with interrupt handling and established
priorities.

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