CosmOS had 1,161 bytes of Program Memory left before the address applications load at, and Tab completion is not going to fit in that with anything to spare. So the wall moves up one page: the system keeps below 0x4FFF and 0x2FFF, and an application is based at 0x5000 and 0x3000. A PAGE IS A CHEAP THING TO GIVE IT AND AN EXPENSIVE THING TO RUN OUT OF. An application still has 44K of Program Memory before the vector table and the largest one here uses 7.5K, so what was taken from applications is space nothing has ever asked for - while what the system gained is the difference between building the next thing and counting bytes while building it. Not doubling, which was the version that would have cost application space worth minding. One page, and the same again when it is needed. Nothing in the machine knows where the wall is, so this is 34 #Base lines, one threshold in the fault handler, and the table in the CosmOS README that Tests/docs.sh reads its limits out of. The native assembler's scratch map had to move with it, and docs.sh said so before anything ran: its data reached 0x40D6 and its buffers began at 0x4000, so they were sitting on its variables. That file already carries a paragraph about the floor coming up and the map staying where it was. It has happened twice now, and been caught by a check the first time wrote. Twenty three recordings are the same runs a page higher. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
86 lines
1.3 KiB
NASM
86 lines
1.3 KiB
NASM
; A Fibonacci number generating program that uses two bytes to store the value.
|
|
|
|
#Include services.asm
|
|
|
|
#Program
|
|
|
|
#Base 0x5000
|
|
|
|
start:
|
|
; Swap ValueB and ValueA.
|
|
; First, store ValueA on the stack.
|
|
SETD ValueA
|
|
LDA
|
|
PSHA
|
|
INCD
|
|
LDA
|
|
PSHA
|
|
; Now copy ValueB into AB.
|
|
SETD ValueB
|
|
LDA ; High byte
|
|
INCD
|
|
LDB ; Low byte
|
|
; Now save it back to ValueA
|
|
SETD ValueA
|
|
STA ; High byte
|
|
INCD
|
|
STB ; Low byte.
|
|
; Now retrieve value A from the stack and store it in ValueB.
|
|
POPB
|
|
POPA
|
|
SETD ValueB
|
|
STA
|
|
INCD
|
|
STB
|
|
; Print ValueA.
|
|
SETD ValueA
|
|
LDA
|
|
CALL printByteHex
|
|
INCD
|
|
LDA
|
|
CALL printByteHex
|
|
CALL blankSpace
|
|
; Now add ValueA and ValueB, and store the result in ValueA.
|
|
; Add the low bytes of ValueA and ValueB
|
|
SETD ValueB
|
|
INCD
|
|
LDA
|
|
SETD ValueA
|
|
INCD
|
|
LDB
|
|
CCF
|
|
ADD
|
|
; Store the result in ValueA.
|
|
STQ
|
|
; Now add the high bytes of ValueA and ValueB.
|
|
DECD
|
|
LDB
|
|
SETD ValueB
|
|
LDA
|
|
ADD
|
|
; If this addition overflows, we're done.
|
|
BRC end
|
|
; Otherwise, store the result in ValueA.
|
|
SETD ValueA
|
|
STQ
|
|
; And branch back to the beginning of the loop.
|
|
BRI start
|
|
end:
|
|
CALL lineFeed
|
|
RSTA
|
|
SWI osExit
|
|
|
|
#Data
|
|
|
|
#Base 0x3000
|
|
|
|
ValueA:
|
|
; Low byte, high byte.
|
|
0x00 0x01
|
|
|
|
ValueB:
|
|
; Low byte, high byte.
|
|
0x00 0x00
|
|
|
|
#Include print.asm
|