| Hi Larry, you should read as well the T9 Instruction Set Manual p.97ff. Best rgds, Uwe. Gesendet mit meinem HTC ----- Reply message ----- Von: "Larry Dickson" <tjoccam@xxxxxxxxxxx> An: "Occam Family" <occam-com@xxxxxxxxxx> Betreff: Question on T9000 Datum: Do., Dez. 22, 2016 22:21 Hello all, I don’t know who to address this to, so I will ask you all. Is there someone out there who worked on the T9000 protected mode system? I picked up a copy of "THE T9000 TRANSPUTER HARDWARE REFERENCE MANUAL� at and looked at the communication instructions in, out, etc. (p 95). They were all marked P (Instruction not allowed in P-process). By contrast, move was marked M (Invalid memory-address for P-process), as were ldnl, stl, stnl, etc. Thus, the latter are legal given good addresses, and the former are not legal even if addresses are good, despite the famous CSP equivalence of b := a and chan c : PAR c ! a c ? b Why are the communications illegal? Was it because only one "current process� is allowed, or was it too hard to keep control over virtual memory while waiting for the second process, or was development effort too great for something which does not exist in C-language user-space? Was communication off-loaded to the L-process belonging to that P-process, or was it just not modeled? By the way, thank you everyone who helped me to a copy of Michael Poole’s ETC paper in WoTUG-21. The book arrived, and has several other treasures besides ETC. For instance, “An optimizing multiprocessor occam system for the PowerPC� has true interrupt-level high priority, simple edge links, and even an extension of the configuration (.PGM) files! Larry Dickson
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