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Shawn Quick
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Move the assembler to src/qasm. qlink links OMF 1.0 and 2.0 from a script. makeBin flattens a load file, qomf dumps OMF, and qpro builds ProDOS volumes. APW and MPW assemble through the ORCA front end. Relocatable modules emit OMF objects. Listings stay off unless -l is set. make boot assembles the GS/OS 6.0.1 ProDOS 8 kernel and BASIC.SYSTEM into an 800K volume. BASIC.SYSTEM accepts ls and pfx, and its splash reports PRODOS BASIC 2.0, copyright 1983-2026. IIGS.601.SRC is the source and the BASIC.SYSTEM oracle that image is built from.
1 line
3.2 KiB
Plaintext
1 line
3.2 KiB
Plaintext
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ProDOS 8 Loader Code Expansion Notes by Monte Benaresh
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May 19, 1989
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Revised May 23, 1989 by Monte Benaresh
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ABOUT THIS DOCUMENT
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This document contains my log of steps taken to expand the "loader" portion of the
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"P8" file on the GS/OSª System Disk. This portion of code gets executed when P8 is
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loaded into the machine and is then discarded once ProDOS is installed into the machine
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(assuming the installation is successful). This code includes special-cased routines
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to set up the environment and to relocate the various drivers and managers to their
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final execution locations. This code also displays the splash screen, identifies
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online devices, and loads the ".SYSTEM" file.
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The loader portion of the code is of predefined size and is currently $B00 bytes long.
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This fact is hard-coded in some of the P8 sourcecode and in the makefile, so expansion
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of this area is a non-trivial task that presently requires some changes to be made by
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hand. This document is intended to be a log of those changes so that subsequent
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attempts to expand the loader section will require the engineer to merely use this
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document as a cookbook-type guide. Better yet, the aforementioned interdependencies
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could be bound by the build system so that expansion of the loader portion would be
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automated.
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This task is motivated by a need to make room for a patch which will support programs
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which run under ProDOS 8 and which make QuickDraw2 calls. This patch fixes a bug in
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the 5.0 System Disk where QuickDraw makes GS/OSª calls without first checking that the
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System is installed in the machine. The patch installs code which is vectored into
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the GS/OSª entry points and returns an error for GS/OSª calls. This fixes things
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because QuickDraw handles errors properly.
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The patch is run during the load/setup phase of starting P8. The loader code checks
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that the current machine is a GS and that P8 is being booted directly, i.e., not
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being installed by GQuit. The patch disables interrupts (for no specific reason,
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only as a precaution), switches the machine to native mode, allocates memory for
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the "real" GS/OS patch, copies that code into the allocated memory, sets up both
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GS/OSª entry points to point to their appropriate pieces of the code, restores the
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environment and then returns to the P8 loader code.
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This change is documented in rev note #101 in the P8 mlisrc.aii file.
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NOTES
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file; PROC; location changes
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-------------------- -------
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ram.n; PROC RAM1; label "SRCE" (2 places) "EQU $2B00" becomes "EQU $2C00"
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ram.n; PROC RAM2; proc header "ORG $2B00" becomes "ORG $2C00"
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mlisrc.aii; before PROC PROCONE; label "ram_1" "equ mli_0+$b00" becomes "equ mli_0+$C00"
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Hex addresses in comments on following
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equates should be updated.
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mlisrc.aii; PROC PROCONE; label "ram_1" exact duplicate of above change
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mlisrc.aii; PROC PROCONE; label "loader_end" from here to the end of the proc (ENDP):
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"$B00" becomes "$C00"
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"$2B00" becomes "$2C00"
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make.p8; build commands for "ram.bin" "-lseg RAM2 -org $002B00" becomes
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"-lseg RAM2 -org $002C00"
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make.p8; build commands for "{workfolder}p8" in "Overlayiigs" commands, all hex values
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after a "-a" directive must be augmented
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by $100, e.g., "-a $2F36" becomes
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"-a $3036"
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