Files
SplitBit-Emulator/Tests/expected/cosmosMonitor.out
T
AnachronautandClaude Opus 5 fd9c4c75f8 Tell the person where it hurts
A fault stopped the machine and printed a line to standard error. On a terminal
that is a diagnosis. Behind a window it is a frozen picture and no reason at
all, because the message went somewhere nobody was looking - the machine looked
hung and was not. It had stopped, and said so invisibly.

CosmOS catches all five faults now and says what happened on the screen, with
the address, in red.

A FAULT ENDS THE PROGRAM, NOT THE MACHINE. That is the answer to "carry on or
start again", and it is not a compromise: a bare RETI from most of these meets
the instruction that failed and fails again, so carrying on was never on offer.
But the machine is almost never what is broken. Everything the shell puts back
when a program exits - the Stack, its vectors, the drive, the working directory,
the console, the screen - is exactly what wants putting back after one dies, so
the handler sets a status and joins handleExit. You are back at the prompt, and
the program is recorded as having STOPPED rather than finished, because saying
"finished" under a red fault message would be the shell contradicting itself.

A fault below where programs load is the system's own, and there is nothing to
go back to. That one says so and stops.

THE SCREEN GOES BACK TO A MODE TEXT CAN BE SEEN IN, and that is the part that
matters rather than the part that is prettiest. A program that faulted in bitmap
mode left the console with no text rows, so it draws nothing at all: the message
would be perfectly correct and completely invisible, which is the one thing it
must never be. Two palette entries go back for the same reason, since a program
that wrote its own colours can leave every ink the same as every paper. Only the
two the message needs, so the rest of what the program chose is left alone.

Both halves are checked by looking at the PICTURE, because the serial line was
never where the problem was. Crash blind ruins the palette and drops into bitmap
mode before it faults; without the mode the screen comes back 320 by 200 with
nothing on it, and without the palette it is the right size with the message
present and unreadable. Each break loses the red on its own.

Crash is also a program worth having: it breaks in whichever of the five ways
you name, so a fault screen can be looked at without having written a bug first.

Two things found on the way:

The native assembler keeps its OWN copy of the reserved vector names, so it did
not know NoHandler or NoDevice and built a cosmos.bin that differed from the
host assembler's. Caught by native.sh, which is exactly the drift that test
exists for.

And cosmosMonitor had dead input. It assembles code into 0x8000 and runs it, and
that code faults - which used to kill the machine, so everything after it in the
file had never run. It runs now, and the recording grew by sixty lines of
monitor session that had been unreachable since the day the fault was put there.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
2026-09-01 15:08:20 -04:00

124 lines
3.0 KiB
Plaintext

CosmOS
> monitor
x examine, d disassemble, a assemble, s set, b bank, g go, exit leaves
* b nonsense
b <program|data|number>
* b 9
there is no such bank
* load greet.sbx
loaded, starting at 4000
* b program
bank 00
* d 4000
4000 47 00 20 00 SETD.0 2000
4004 72 10 SWI 10
4006 47 00 20 44 SETD.0 2044
400A 72 10 SWI 10
400C 47 00 20 7A SETD.0 207A
4010 27 1F INIB 1F
4012 72 11 SWI 11
4014 47 00 20 5D SETD.0 205D
* x 4000
4000 47 00 20 00 72 10 47 00 20 44 72 10 47 00 20 7A G. .r.G. Dr.G. z
4010 27 1F 72 11 47 00 20 5D 72 10 47 00 20 7A 72 10 '.r.G. ]r.G. zr.
4020 47 00 20 65 72 10 20 72 12 00 00 00 00 00 00 00 G. er. r........
4030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
* b data
bank 01
* x 2000
2000 61 20 70 72 6F 67 72 61 6D 2C 20 6C 6F 61 64 65 a program, loade
2010 64 20 6F 66 66 20 61 20 64 69 73 6B 2C 20 72 75 d off a disk, ru
2020 6E 6E 69 6E 67 20 6F 6E 20 74 68 65 20 73 79 73 nning on the sys
2030 74 65 6D 20 74 68 61 74 20 6C 6F 61 64 65 64 20 tem that loaded
* b 2
bank 02
* x 0
0000 01 FF 00 00 00 00 00 00 01 FF 00 00 00 00 00 00 ................
0010 03 FF 08 00 00 00 00 00 01 20 01 00 00 00 00 00 ......... ......
0020 00 FF 00 00 00 00 00 00 00 FF 00 00 00 00 00 00 ................
0030 00 FF 00 00 00 00 00 00 00 FF 00 00 00 00 00 00 ................
* s 0 FF
that bank will not be written
* b program
bank 00
* s 8000 26 48 D1 00 26 0A D1 00 18 12
* d 8000
8000 26 48 INIA 48
8002 D1 00 OUTA 00
8004 26 0A INIA 0A
8006 D1 00 OUTA 00
8008 18 SHR
8009 12 AND
800A 00 ?
800B 00 ?
* g 8000
H
that byte is not an instruction, at 800A
A 85 B 3F Q 05
the program was stopped
* d 8000
8000 26 48 INIA 48
8002 D1 00 OUTA 00
8004 26 0A INIA 0A
8006 D1 00 OUTA 00
8008 18 SHR
8009 12 AND
800A 00 ?
800B 00 ?
* b data
bank 01
* s 8100 68 65 6C 6C 6F 2C 20 74 79 70 65 64 0A 00
* b program
bank 00
* a 8200
8200: SETD.0 8100
8204: SWI 10
8206: lda.2
8208: LDD.0.1
820B: frobnicate
no such instruction
820B: INIA
that one needs a value after it
820B: SWI 12
820D: .
* d 8200
8200 47 00 81 00 SETD.0 8100
8204 72 10 SWI 10
8206 42 02 LDA.2
8208 4A 00 01 LDD.0.1
820B 72 12 SWI 12
820D 00 ?
820E 00 ?
820F 00 ?
* g 8200
hello, typed
finished
* exit
> dir
greet.sbx 211
hello.sbx 53
Life.sbx 1396
Snake.sbx 2164
Keys.sbx 664
Say.sbx 156
Break.sbx 149
Grid.sbx 559
Press.sbx 872
Mode.sbx 48
Crash.sbx 632
notes.txt 21
Apps <dir>
hi.script 121
bad.script 45
plain.script 24
cross.script 280
nonl.script 38
outer.script 376
inner.script 44
loop.script 35
20 files, 1 directory
> exit
halted
Execution halted.
[exit 0]