🚀 go-pugleaf

In article <1414.25C69DAC@busker.FIDONET.ORG>, Howard.Spindel@p8.f14.n105.z1.FIDONET.ORG (Howard Spindel) writes:
>> In an article of <27 Jan 90 00:25:32 GMT>, jmerrill@jarthur.Claremont.EDU (Jason Merrill) writes:>> 
>>I've found that disk caches intefere with communications; I have a 19200

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> This problem may be somewhat alleviated by using 16550 UART chips as
> they have internal buffering.  The problem does not exist with 386
> machines.

Wrong! At least one 386 from IMC has the problem. (It's 25Mhz 80386).
Replacing the 16450 to 16550 solves the problem.
 
I think the problem is most common if you have an RLL or other hd-controller
with own bios. The interrupts to the AT-bios, the hd-bios and to the 
cache-driver takes too long time and you lose chars.
(You transfer some file, the transferprogram will save a block to disk.
Use the dos-interrupt for disk transfer, the cache-driver gets the block to
store it on the cache-memory. The cache-routine goes to the HD-bios and the
HD-bios works. If that takes more than 520 us, you lose chars.