more help from Athanasios Pavlidis

This commit is contained in:
Perry Kivolowitz 2023-01-16 07:19:50 -06:00
parent c5389fa7b1
commit 67581d5435
7 changed files with 26 additions and 5 deletions

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@ -24,6 +24,7 @@
"pimm", "pimm",
"pseudocode", "pseudocode",
"regs", "regs",
"setfill",
"simm", "simm",
"smaddl", "smaddl",
"stringstream", "stringstream",

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@ -156,7 +156,7 @@ on a little endian machine, it is the first byte in the long in memory.
## Output on a big endian machine ## Output on a big endian machine
We tried and tried to find a kind soul to run the above program on a We tried and tried to find a kind soul to run the above program on a
big-endian machine. Redditor Athanasios Pavlidis ran a C version of the big-endian machine. Athanasios Pavlidis ran a C version of the
code on both an Amiga A4000/MC68040 and an Amiga A3000/MC68030. The code on both an Amiga A4000/MC68040 and an Amiga A3000/MC68030. The
results were: results were:
@ -170,9 +170,18 @@ i64: 89abcdef01234567
Notice the values for `i16` and `i32` match the right hand column above. Notice the values for `i16` and `i32` match the right hand column above.
The value for `i64` is borked in that we specified it in the C code as a The value for `i64` is borked in that we specified it in the C code as a
`long`. We then tried specifying the `long` as a `long long`. Apparently `long`. We then tried specifying the `long` as a `long long` but got the
there is little support for 64 bit numbers on this ancient but same results.
venerable architecture.
Mr. Pavlidis tried a different tool chain and got the correct results.
Here is a screenshot:
![screen](./amiga.png)
For completeness, Mr. Pavlidis run the code on the IBM Power PC
(System/6000) and got these correct results:
![screen](./power.png)
Athanasios Pavlidis has our appreciation and thanks. Athanasios Pavlidis has our appreciation and thanks.
@ -197,3 +206,14 @@ The common Intel processors are also little-endian.
## So what's big-endian? ## So what's big-endian?
IBM mainframes and the Motorola 68K family come to mind. See above. IBM mainframes and the Motorola 68K family come to mind. See above.
## Nostalgia
The author worked extensively in the Amiga ecosystem from the middle
1980s to the middle 1990s. Here are some products from his company:
![Art Department Professional](./adpro.jpeg)
![mp](./mp2.webp)
In those days we sold software by the pound! Look at that manual!

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