31 lines
1.4 KiB
Plaintext
31 lines
1.4 KiB
Plaintext
AST RESEARCH TECHNICAL BULLETIN TB-0297 9-11-87
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AST Hotshot Using 8086/88 Device Drivers
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Due to the fact that the AST Hotshot uses an 80286 microprocessor
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chip in its design, a compatibility problem may exist with device
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drivers written for the 8086/88 microprocessor. The 80286 does
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not allow an OUT instruction to be followed by another I/O
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instruction, unless the OUT is immediately followed by a JMP
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SHORT $+2 instruction to introduce an I/O wait state. Many of
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the 8088/86 device drivers were written before the 80286 was
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introduced and do not contain correct 80286 coding techniques.
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Hence, these drivers may cause system hangs or other problems
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when the device for which they were written is accessed when in
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the Hotshot 80286 mode. This is not to be considered a Hotshot
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failure but a coding problem within the driver itself.
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Compatibility problems of this type is the reason that the
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Hotshot has an 8088 mode of operation. Most new drivers are
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written using 80286 coding techniques which will work on both
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chip types.
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A known problem exists with the Microsoft Version 6.00 or older
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mouse drivers MOUSE.SYS or MOUSE.COM when used with the Hotshot
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board in 80286 mode. The system may hang or cause an incorrect
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display when high mouse I/O activity is present with other I/O
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operations, i.e. disk reads and writes. Microsoft is aware of
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the problem and is going to update the mouse drivers.
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