[vcf-midatlantic] Looking for a TI Silent 707 1200baud for the VCF Museum

Jameel Akari jakari at bithose.com
Fri Oct 14 14:30:37 EDT 2016

On Fri, 14 Oct 2016, David Williams via vcf-midatlantic wrote:

> On 14/10/2016 15:00, Neil Cherry wrote:
>>  On 10/14/2016 09:46 AM, David Williams via vcf-midatlantic wrote:
>> >  Just tried dumping a text file to my 703 at 1200 baud and you're right, 
>> >  after about 500
>> >  characters or so, it can't keep up with the input. Is there any way to 
>> >  put a delay after
>> >  characters / line on Simh? I tested again by dumping the same text file 
>> >  via TeraTerm using
>> >  a 15ms delay per character and 350ms per line and it seemed to work 
>> >  fine.
>>  Don't the RS232 control leads take care of this?
> They should but I don't believe they are present of the RPi board

They sort of exist on GPIO #30 and #31, but their use is not standard, and 
your typical level shifter only does TX/RX.  I just went through this on a 
recent project with a RPi connected to an (actual) VT100 -- Couldn't go 
faster than 4800 baud and expect it to work at all, and even there users 
typing on the terminal could cause spurious escape characters to be 

I am thinking of redoing mine with a standard USB-to-serial dongle... 
wouldn't get the Pi kernel console there, but I could still have a getty.

Incidentally the RF environment within the VT100 itself is more than the 
Pi's 3.3v single-ended external I/O can handle. ;)

Jameel Akari

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