On 10/4/24 00:07, Christian Corti via cctalk wrote: > On Wed, 2 Oct 2024, Tom Gardner wrote: >> Speaking of high profit margins: on the 1620, there was an extra cost >> option called "direct seek". I don't know if involved a jumper cut or >> some actual circuitry (an adder, most likely). We didn't have that, >> and the result is that a seek from cylinder x to cylinder y was done >> by a full retract to cylinder 0, followed by a seek out to y. It was >> amusing to watch the shaking resulting from a simple "incrementing >> seek test" -- seek to cylinder i for i = 0 to 99. Those last few >> seeks would take the better part of a second. > > Here's a link to a video that I took last year of a 1311 doing seeks (it > is running on a 1401): https://www.youtube.com/watch?v=LXDVRP9pfyw
We did not have the direct seek feature on the 1311 on our CADET back then. Figure that it takes additional logic to figure out "where am I now and where do I want to go?" So, a feature. --Chuck
