asm v2.2, YACC1 port¶

Michael H. Riley's table-driven cross assembler (upstream/rcasm-2.2/ is his unmodified 2.2 with the .def tables for other CPUs). The YACC1 port (2020-08 → 2021-07-09) changed asm.c asmcmds.c support.c mstrings.* header.h Makefile rcasm.rc and added yacc1.def, the YACC1 instruction table. asm.txt / asm.doc = the manual.

Its twins on the machine (2026-09-25): /BIN/ASM (os/commands-asm/asm.asm, YACC1 assembly, since 2026-09-26) and /BIN/ASMC (os/commands/asm.c, its specification) assemble the same dialect under Y1/OS with the instruction tables generated from yacc1.def (tools/gen_y1_optab.py, run by os/Makefile), so a change here reaches them on the next make -C os; tests/asm/run.py checks the three agree on every source in the tree (docs/programming/ASSEMBLER.md section 10).

yacc1.def here is the 2025-03-14 version: the 2020-11-25 table plus a lowercase equ directive (the only difference); it is what firmware/monitor/monnew-2025/ was assembled with. Build: make (plain Makefile, 2026-09-20; the NetBeans one is Makefile.netbeans). make check assembles the monitor and BASIC sources from firmware/ in build/ and diffs the images and the ROM against the committed ones; make install copies a fresh build into firmware/ when a source was changed on purpose. Run the assembler from a folder containing rcasm.rc.

Quirks worth knowing (probed 2026-09-22 for the C compiler): source lines are upper-cased, so labels are case-insensitive and DB "text" emits upper-case text (emit bytes as numbers); labels are at most 29 characters (30+ crashes it); a leading - on a number is silently dropped (LDAI -1 assembles as 01); label+4, label*2, (label+4).0/.1 (low/high byte) work, label+4.0 does not; a \B operand over 255 is an error. Fixed 2026-09-22 (tools/patched_files.txt): bytes after a DS were appended to the Intel-hex record that started before the DS and so loaded at the wrong address — DS now flushes the record like ORG (the firmware never uses DS; make check still reproduces the ROM).

Moved out of here 2026-09-20 (this folder used to be the working directory for everything): - monitor/BASIC sources, listings, images and rom → firmware/ (the copies here were the git-HEAD "not working" 3bcacf3 build, now firmware/*/candidates/2021-09-02-3bcacf3-not-working/); basic.asmtmp copy (Nov-2020 port draft) → firmware/basic/candidates/2020-11-10-port-draft/. - yacc1test.asm (the CPU test program) and its 15 dated 2020 snapshots → tests/assembler/. - old/rcasm, old/rcasm-old (intermediate stages of the port, with compiled binaries) → archive/superseded-revisions/assembler-port-2020/. - old/a18* (Riley's A18 1802 assembler, CUG149 – RC/asm's ancestor, not YACC1 work) → archive/third-party/. - dropped: abc (a symbol listing), list (a run log), c_standard_headers_indexer.c (Xcode artefact).