[HECnet] Which is THE dec printer?

[Cory Smelosky]

On Wed, 15 Jan 2014, Dave McGuire wrote:

On 01/15/2014 06:42 PM, Cory Smelosky wrote:
A lot of people (myself included) insisted on direct-in-the-bus
printer controllers when we saw how badly serial printers tanked the
system when we connected them to DZ11s. ;)

Oh I can imagine that.   A dedicated controller would have MUCH higher
bandwidth than the <1.5mbitcapable on the DZ11. ;)

It's the interrupt load that's the problem.   It could TANK an 11/750.

Didn't the DZ11 depend on the CPU for interrupts?

Every interrupt depends on the CPU. ;)


True...but offloading helps cut down on the other stuff it needs to process. ;)

Isn't that why say...the DHV11 had processors to offload serial
processing to?

The DHV11 has a pair of 8051s on it.   The DH11 is several boards full
of logic.   It has buffering and DMA capability to offload the host
system...it needs much less hand-holding than the DZ11.


Ahh.   I thought it was something like that.

                            -Dave



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Cory Smelosky
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