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-rw-r--r--source/blog/yax/arch/rx.md36
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diff --git a/source/blog/yax/arch/rx.md b/source/blog/yax/arch/rx.md
index 237d4de..1195981 100644
--- a/source/blog/yax/arch/rx.md
+++ b/source/blog/yax/arch/rx.md
@@ -51,6 +51,42 @@ meticulously?
instruction encodings are listed in alphabetic order of instruction mnemonics. this is not amenable to writing a disassembler.. so i went through all three versions of the manual and transcribed encodings *from* the manual into a text file i could easily reorder. and so [notes/encoding_table](https://github.com/iximeow/yaxpeax-rx/blob/no-gods-no-/notes/encoding_table) was born. reorder that to be approximately by bits, and [notes/reordered_encodings](https://github.com/iximeow/yaxpeax-rx/blob/no-gods-no-/notes/reordered_encodings). finally, i tried finding patterns across encodings and simplifying the total number of encodings across all instructions, and that left me with [notes/grouped_encodings](https://github.com/iximeow/yaxpeax-rx/blob/no-gods-no-/notes/grouped_encodings).
+vendors! please do not make me write things like this!! i'm not good at it!!!
+```
+0 0 0 0 0 1 1 0 | mi [ opc ] ld | [ rs ] [ rd ] SUB src, dest (v1, v2, v3)
+ 0 0 => B 0 0 => [Rs]
+ 0 1 => W 0 1 => dsp:8[Rs]
+ 1 0 => L 1 0 => dsp:16[Rs]
+ 1 1 => UW 1 1 => Rs
+ opc={sub, cmp, add, mul, and, or, X, X, see below}
+
+0 0 0 0 0 1 1 0 | mi 1 0 0 0 ld | 0 0 0 [ opc ] | [ rs ] [ rd ] SBB src, dest (v1, v2, v3)
+ 1 0 => L
+ _ _ => invalid
+ 00 => [Rs]
+ 01 => dsp:8[Rs]
+ 10 => dsp:16[Rs]
+ opc={
+ sbb(mi=10,ld!=11), X, adc(mi=10,ld!=11), X,
+ max, min, emul, emulu,
+ div, divu, X, X
+ tst, xor, X, X,
+ xchg, itof, X, X,
+ X, utof(v2, v3), X, X,
+ X, X, X, X,
+ X, X, X, X,
+ }
+
+0 0 0 0 1 [dsp] BRA.S src (v1, v2, v3)
+
+0 0 0 1 c [dsp] BCnd.S src (v1, v2, v3)
+ 0 => beq/bz (src = if dsp > 2 { dsp } else { dsp + 8 })
+ 1 => bne/bnz
+
+0 0 1 0 [ cnd ] | [ pcdsp ] BCnd.B src (v1, v2, v3)
+ cnd => {eq, ne, geu, ltu, gtu, leu, pz, n, ge, lt, gt, le, o, no, bra.b, Reserved}
+```
+
the disassembler itself is largely transcription of this table into source code. including, unfortunately, a massive chain of if/else from `0b00000000` stopping at dozens of points on the way to `0b11111111`. :')
# encoding notes