success!  for the most part this yields clean transmission. From time to
time I think there is a buffer overrun due to BASIC being slow.   or maybe
the link corrupts, don't know yet.  It might lose sync.

T200 ---> T200 @76800

source:
10 open "COM:78n1enn" for output as 1  : REM make port look like 4800
20 out 207,64 :REM reset the uart
30 out 207,77 : REM async x1 mode 8 n 1, boost port by 16 x to 76800
40 out 207,37 : REM turn on the interface
50 print#1,"this is a test":goto50

destination
10 open "COM:78n1enn" for input as 1
20 out 207,64
30 out 207,77
40 out 207,37
50 input#1,a$:print a$:goto50




On Sat, Jun 2, 2018 at 3:17 PM, John R. Hogerhuis <[email protected]> wrote:

>
>
> On Sat, Jun 2, 2018 at 11:16 AM, Stephen Adolph <[email protected]>
> wrote:
>
>> It looks like the T200  puts the 82c51 into async x16 at address 8713h in
>> the rom.   (out C8 where a =4Eh
>>
>> clock has to be 5x faster in this mode, so for 76800 we'd need a clock
>> rate of 76800x16x5 = 6.144MHz.  clearly.. not going to work.
>>
>> However if we put the 82c51 into x1 mode it could work.
>>
>> I think the sequence is something like
>>
>> mvi a,40h
>> out C8h -- reset the chip
>>  mvi a,4D - 1 stop bit, no parity, 8 bits, 1x mode
>>
>> one would still have to set the clock divider registers separately.
>>
>>
>>
> Ok, that sounds promising at least. I don't know what the async x1 and x16
> modes are... I guess it didn't come up in setting bps on the Model 10x.
>
> -- John.
>

Reply via email to