[HECnet] TOPS-10 KS10 Ethernet Monitor

[Cory Smelosky]

On Sun, 26 Apr 2015, Johnny Billquist wrote:

> All true and good points.
> I'm curious on exactly how a DEUNA/DELUA works in a KS-10. Does anyone know? 
> Does it do 8-bit-byte DMA to the 18-bit memory, leaving the top two bits 
> alone. Or does it only work if it do word DMA (would be strange, as the 
> controller itself can send and receive odd byte length ethernet packets).
>
> And how does the whole controller actually work in a KS, since the controller 
> expects there to be control structures in memory, which are used to manage 
> the buffers. Those are expected to be 16-bit fields at one address, and an 
> additional 2 bits of address in another word.
>
> Is there some potential problem with regards to a PDP-11, which have two 
> parity bits for data, which are used for actual data on a KS? (If I remember 
> right.)
>

How does the DZ do it?  THAT I know is a supported.

> In short, this is not trivial, and if it works on a real machine, the 
> emulation needs to reflect that truthfully, or else it will not be so useful. 
> I suspect it should work on a real machine, as hints suggested that it was at 
> least considered.
>

Could always do "emulation mode" and "real hardware mode".

> 	Johnny
>
>

-- 
Cory Smelosky
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