Unterschiede
Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
Nächste Überarbeitung | Vorhergehende Überarbeitung | ||
analyticalengine:destructiveload [2015-04-20 22:19] – created rainer | analyticalengine:destructiveload [2015-08-20 13:47] (aktuell) – Layout korrigiert rainer | ||
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In the sketch, it is mentioned at various places: | In the sketch, it is mentioned at various places: | ||
- | | + | |
- | * p. 680: //But as these numbers are each to be used again in another operation, they must again be inscribed somewhere; therefore, while the mill is working out their product, the machine will inscribe them anew on any two columns that may be indicated to it through the cards; and as, in the actual case, there is no reason why they should not resume their former places...// This is highly misleading (and not corrected in the notes), as it seems to require additional cards to transfer any input value to any storage cell while the mill is working. | + | |
- | * p. 708: // In order to provide for the one or the other of the courses above indicated, there are two varieties of the Supplying Variable-cards. One of these varieties has provisions which cause the number given off from any Variable to return to that Variable after doing its duty in the mill. The other variety has provisions which cause zero to be substituted on the Variable, for the number given off. These two varieties are distinguished, | + | * p. 680: //But as these numbers are each to be used again in another operation, they must again be inscribed somewhere; therefore, while the mill is working out their product, the machine will inscribe them anew on any two columns that may be indicated to it through the cards; and as, in the actual case, there is no reason why they should not resume their former places...// |
+ | * p. 708: //In order to provide for the one or the other of the courses above indicated, there are two varieties of the Supplying Variable-cards. One of these varieties has provisions which cause the number given off from any Variable to return to that Variable after doing its duty in the mill. The other variety has provisions which cause zero to be substituted on the Variable, for the number given off. These two varieties are distinguished, | ||
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However, from Bromley' | However, from Bromley' | ||
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Note that information is destructively readout with many types of storages, in particular core memory and dynamic RAM cells. However, the later solution was to provide one set of wheels for each ingress shaft, and write it back while the mill works, instead of duplicating the whole memory. With core memory, this did slow down the CPU, thus the memory was splitted in even and odd banks, slowing down the CPU only if two even or odd addresses where used in direct succession. | Note that information is destructively readout with many types of storages, in particular core memory and dynamic RAM cells. However, the later solution was to provide one set of wheels for each ingress shaft, and write it back while the mill works, instead of duplicating the whole memory. With core memory, this did slow down the CPU, thus the memory was splitted in even and odd banks, slowing down the CPU only if two even or odd addresses where used in direct succession. | ||
- | The ENIAC with its decimal shift registers would have had the same problem, but instead of shifting down to zero and counting, it shifted up circulary and counted the number of places shifted out on top. This would have been possible for the AE too, by turing the toothed wheel (indicated by 3 in Fig.1 of Bromley) a hole circle, and using the turn of the axis A (indicated by 2) instead. Clearly this would be done differently, | + | The ENIAC with its decimal shift registers would have had the same problem, but instead of shifting down to zero and counting, it shifted up circulary and counted the number of places shifted out on top. This would have been possible for the AE too, by turing the toothed wheel (indicated by 3 in Fig.1 of Bromley) a whole circle, and using the turn of the axis A (indicated by 2) instead. Clearly this would be done differently, |