[Coco] CoCoNet status

[Roger Taylor]

At 10:29 PM 12/6/2008, you wrote:

>Roger,
>
>Have you tested this with a CoCo 1?  Recent tests I've done have led
>me to the conclusion that the CoCo 1 hardware is not capable of
>transmitting 57600 bps through the bit banger port, although it can
>receive data at that speed. My guess is that the opamp used for the
>level translation to +/- 12 volts can't operate that fast.  You will
>probably have to lower the transmission speed or specify a CoCo 2 as
>the minimum requirement.
>
>Darren


I confirmed that the PC is not receiving correctly at 57600 bps from 
both of my CoCo 1 systems.  You can see junk bytes being received 
instead, but it looks like the same number of bytes, just not the 
data that was sent.  115200 bps obviously didn't work, either.

Another thing I noticed.  When you turn a CoCo on, it "transmits" a 
phantom character to the remote PC due to how BASIC sets up the PIA 
chips.  At some point a start bit is seen by the PC which leads to a 
byte being framed.  It could be that a break or partial break is 
transmitted.  I haven't looked further into it.


-- 
Roger Taylor

http://www.wordofthedayonline.com