Talk:Calendar - for "REAL" programmers: Difference between revisions
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(added a new talk section for some BCD computers.) |
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==Delete?== |
==Delete?== |
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Far too specific. --[[User:Paddy3118|Paddy3118]] 03:35, 31 May 2011 (UTC) |
Far too specific. --[[User:Paddy3118|Paddy3118]] 03:35, 31 May 2011 (UTC) |
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:Looks like maybe it's just for fun maybe. I suggest removing the task tag and moving it to a subpage of the user who made it's user page. --[[User:Mwn3d|Mwn3d]] 03:45, 31 May 2011 (UTC) |
:Looks like maybe it's just for fun maybe. I suggest removing the task tag and moving it to a subpage of the user who made it's user page. --[[User:Mwn3d|Mwn3d]] 03:45, 31 May 2011 (UTC) |
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===Examples=== |
===Examples=== |
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;Example 12-bit computer architectures |
;Example 12-bit computer architectures |
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*[[wp:PDP-8|PDP-8]] |
*[[wp:PDP-8|PDP-8]] |
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[[User:NevilleDNZ|NevilleDNZ]] 05:04, 31 May 2011 (UTC) |
[[User:NevilleDNZ|NevilleDNZ]] 05:04, 31 May 2011 (UTC) |
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=== Discussion Cont.=== |
=== Discussion Cont.=== |
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:Not decision, discussion. And you`ve made a great case! --[[User:Paddy3118|Paddy3118]] 05:43, 31 May 2011 (UTC) |
:Not decision, discussion. And you`ve made a great case! --[[User:Paddy3118|Paddy3118]] 05:43, 31 May 2011 (UTC) |
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[[User:NevilleDNZ|NevilleDNZ]] 05:14, 1 June 2011 (UTC) |
[[User:NevilleDNZ|NevilleDNZ]] 05:14, 1 June 2011 (UTC) |
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=== Create another algorithm? === |
=== Create another algorithm? === |
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:The task description says "Create another algorithm", yet the Algol solutions are identical (except for the case).--[[User:Abu|Abu]] 15:06, 31 May 2011 (UTC) |
:The task description says "Create another algorithm", yet the Algol solutions are identical (except for the case).--[[User:Abu|Abu]] 15:06, 31 May 2011 (UTC) |
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I get your drift.... rewording task: Provide an algorithm ... presented entirely without lowercase. ThanX for pointing it out. [[User:NevilleDNZ|NevilleDNZ]] 03:58, 1 June 2011 (UTC) |
I get your drift.... rewording task: Provide an algorithm ... presented entirely without lowercase. ThanX for pointing it out. [[User:NevilleDNZ|NevilleDNZ]] 03:58, 1 June 2011 (UTC) |
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=== Examples, BCD machines === |
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;Example 5-bit computer architectures |
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* [[wp:IBM_1620|IBM 1620]] |
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* [[wp:IBM_1620|IBM 1710]] |
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* [[wp:IBM_1620|IBM 1720]] |
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The '''IBM 1620''' (and the others above) had a magnetic-core memory with BCD encoding. |
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<br>('''BCD''' = '''B'''inary '''C'''oded '''D'''ecimal.) |
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Each memory location was (for the most part) a decimal digit. |
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Each memory location was comprised of five bits: |
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::* a flag bit (the '''F''' bit), used to indicate a negative number, an ''end-of-field'', or a ''carry''. |
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::* four bits (the '''8421''' bits), used to indicate which decimal digit was being represented. |
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Additionally, there was a check bit (the '''C''' bit), which isn't used to hold "data" and could not be set or accessed by a programmer. It was used as a parity bit. Every ''decimal digit'' had to have a odd number of bits set, including the '''C''' bit. If not odd, a "parity bit" error light was lit and the computer went into a wait (stopped) state. |
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There wasn't a method to indicate lowercase letters. |
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Characters used two consecutive decimal digits. |
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There were three special "numbers": |
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::::* '''1010''' a record mark |
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::::* '''1100''' a numeric blank (for punched cards) |
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::::* '''1111''' a group mark |
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All opcodes were two decimal digits. |
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::::::::::::::::::: -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 02:12, 29 October 2020 (UTC) |
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==another ASCII version== |
==another ASCII version== |