From b5dc23579f634914cb932da30f53eac8d26a6703 Mon Sep 17 00:00:00 2001 From: Rikard Nordgren Date: Mon, 7 Apr 2025 22:13:55 +0200 Subject: [PATCH] add atn_FAC1 --- STATUS.md | 2 +- src/basic/math/e30e.atn_FAC1.s | 57 +++++++++++++++++++ src/basic/{,stubs_math => math}/e30e.interop | 0 .../e30e.atn_FAC1.s => math/poly_atn.s} | 18 +----- strings/07A9E0A0E22050B86810034CB4BF60 | 3 + ...7E7E9244993A7E4CCC91C77FAAAAAA138100000000 | 1 + strings/A0B9200FBB | 3 + strings/A0E22050B8 | 3 + strings/A9E0A0E220 | 3 + strings/B9200FBB | 3 + strings/BCA0B920 | 3 + strings/DAA2A56648 | 3 + 12 files changed, 83 insertions(+), 16 deletions(-) create mode 100644 src/basic/math/e30e.atn_FAC1.s rename src/basic/{,stubs_math => math}/e30e.interop (100%) rename src/basic/{,stubs_math/e30e.atn_FAC1.s => math/poly_atn.s} (56%) create mode 100644 strings/07A9E0A0E22050B86810034CB4BF60 create mode 100644 strings/0B76B383BDD3791EF4A6F57B83FCB0107C0C1F67CA7CDE53CBC17D1464704C7DB7EA517A7D6330887E7E9244993A7E4CCC91C77FAAAAAA138100000000 create mode 100644 strings/A0B9200FBB create mode 100644 strings/A0E22050B8 create mode 100644 strings/A9E0A0E220 create mode 100644 strings/B9200FBB create mode 100644 strings/BCA0B920 create mode 100644 strings/DAA2A56648 diff --git a/STATUS.md b/STATUS.md index 53bab291..8fa1ba85 100644 --- a/STATUS.md +++ b/STATUS.md @@ -256,7 +256,7 @@ Floating point mathematical routines - not official, but well known and broadly | `$E264` | `cos_FAC1` | PARTIAL | needs `sin_FAC1` | | `$E26B` | `sin_FAC1` | NOT DONE | some work already started | | `$E2B4` | `tan_FAC1` | NOT DONE | | -| `$E30E` | `atn_FAC1` | NOT DONE | | +| `$E30E` | `atn_FAC1` | PARTIAL | not fully tested yet |
diff --git a/src/basic/math/e30e.atn_FAC1.s b/src/basic/math/e30e.atn_FAC1.s new file mode 100644 index 00000000..9b4d27b1 --- /dev/null +++ b/src/basic/math/e30e.atn_FAC1.s @@ -0,0 +1,57 @@ +;; #LAYOUT# STD * #TAKE +;; #LAYOUT# * BASIC_0 #TAKE +;; #LAYOUT# * * #IGNORE + +; +; Math package - arc tangent of FAC1 +; +; See also: +; - [CM64] Computes Mapping the Commodore 64 - page 211 +; - https://www.c64-wiki.com/wiki/Floating_point_arithmetic +; - https://codebase64.org/doku.php?id=base:kernal_floating_point_mathematics +; - https://www.c64-wiki.com/wiki/ATN + +; Algorithm: +; 1. Save sign of x +; 2. Calculate AX = |x| (we can use that arctan(-x) = -arctan(x) +; 3. If AX > 1 set AX = 1/AX (we can use that arctan(x) = pi/2 - arctan(1/x) ) +; 4. Use polynomial to approximate arctan(AX) now since 0 <= AX <= 1 +; 5. Adjust sign of result and offset with pi/2 if needed as per above + + +atn_FAC1: + lda FAC1_sign ; Save sign of FAC1 on the stack + pha + lda #$00 ; FAC1 = abs(FAC1) + sta FAC1_sign + sta TEMPF1 ; AX not scaled + + lda #const_ONE + jsr FCOMP + bmi atn_skipscale + + lda #const_ONE + jsr div_MEM_FAC1 + inc TEMPF1 ; AX scaled + +atn_skipscale: + lda #poly_atn + jsr poly1_FAC1 + + lda TEMPF1 + beq atn_skipoffset + + lda #const_HALF_PI + jsr sub_MEM_FAC1 + +atn_skipoffset: + pla + bpl atn_out + jmp toggle_sign_FAC1 + +atn_out: + rts diff --git a/src/basic/,stubs_math/e30e.interop b/src/basic/math/e30e.interop similarity index 100% rename from src/basic/,stubs_math/e30e.interop rename to src/basic/math/e30e.interop diff --git a/src/basic/,stubs_math/e30e.atn_FAC1.s b/src/basic/math/poly_atn.s similarity index 56% rename from src/basic/,stubs_math/e30e.atn_FAC1.s rename to src/basic/math/poly_atn.s index 5c5d53f3..da8a2bbc 100644 --- a/src/basic/,stubs_math/e30e.atn_FAC1.s +++ b/src/basic/math/poly_atn.s @@ -1,22 +1,10 @@ ;; #LAYOUT# STD * #TAKE -;; #LAYOUT# * BASIC_0 #TAKE +;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000 +;; #LAYOUT# * BASIC_0 #TAKE ;; #LAYOUT# * * #IGNORE -; -; Math package - arc tangent of FAC1 -; -; See also: -; - [CM64] Computes Mapping the Commodore 64 - page 211 -; - https://www.c64-wiki.com/wiki/Floating_point_arithmetic -; - https://codebase64.org/doku.php?id=base:kernal_floating_point_mathematics -; +; Polynomial for the atn function -; XXX provide implementation - -atn_FAC1: - - +STUB_IMPLEMENTATION - poly_atn: !byte $0B ; series length - 1 diff --git a/strings/07A9E0A0E22050B86810034CB4BF60 b/strings/07A9E0A0E22050B86810034CB4BF60 new file mode 100644 index 00000000..dc79555c --- /dev/null +++ b/strings/07A9E0A0E22050B86810034CB4BF60 @@ -0,0 +1,3 @@ +$07 + LDA #$E0 + LDY #$E2 + JSR $B850 + PLA + BPL $03 + JMP $BFB4 + RTS + +Load address of known constant into YA + call well known floating point function + branch on top of stack and call other well known floating point function. diff --git a/strings/0B76B383BDD3791EF4A6F57B83FCB0107C0C1F67CA7CDE53CBC17D1464704C7DB7EA517A7D6330887E7E9244993A7E4CCC91C77FAAAAAA138100000000 b/strings/0B76B383BDD3791EF4A6F57B83FCB0107C0C1F67CA7CDE53CBC17D1464704C7DB7EA517A7D6330887E7E9244993A7E4CCC91C77FAAAAAA138100000000 new file mode 100644 index 00000000..9680dddc --- /dev/null +++ b/strings/0B76B383BDD3791EF4A6F57B83FCB0107C0C1F67CA7CDE53CBC17D1464704C7DB7EA517A7D6330887E7E9244993A7E4CCC91C77FAAAAAA138100000000 @@ -0,0 +1 @@ +12 floating point numbers making upp the approximation polynomial for the ATN function. This polynomial is described in "Computer Approximations" by John Fraser Hart et al. (ISBN 0-88275-642-7) according to https://www.c64-wiki.com/wiki/POLY1 diff --git a/strings/A0B9200FBB b/strings/A0B9200FBB new file mode 100644 index 00000000..804e875a --- /dev/null +++ b/strings/A0B9200FBB @@ -0,0 +1,3 @@ +LDY #$B9 + JSR $BB0F + +Partially set input and call well known floating point function diff --git a/strings/A0E22050B8 b/strings/A0E22050B8 new file mode 100644 index 00000000..47f18913 --- /dev/null +++ b/strings/A0E22050B8 @@ -0,0 +1,3 @@ +LDY #$E2 + JSR $B850 + +Partial load of input + call to known floating point function diff --git a/strings/A9E0A0E220 b/strings/A9E0A0E220 new file mode 100644 index 00000000..c53b5c2c --- /dev/null +++ b/strings/A9E0A0E220 @@ -0,0 +1,3 @@ +LDA #$E0 + LDY #$E2 + JSR fragment + +Load address of known constant and call some function diff --git a/strings/B9200FBB b/strings/B9200FBB new file mode 100644 index 00000000..9b0a1caa --- /dev/null +++ b/strings/B9200FBB @@ -0,0 +1,3 @@ +$B9 + JSR $BB0F + +Fragment + call to well known floating point function diff --git a/strings/BCA0B920 b/strings/BCA0B920 new file mode 100644 index 00000000..d951ea5b --- /dev/null +++ b/strings/BCA0B920 @@ -0,0 +1,3 @@ +$BC + LDY #$B9 + JMP + +Fragments diff --git a/strings/DAA2A56648 b/strings/DAA2A56648 new file mode 100644 index 00000000..bc36bdde --- /dev/null +++ b/strings/DAA2A56648 @@ -0,0 +1,3 @@ +$DA + $A2 + LDA $66 + PHA + +Fragment + push FAC1 sign on stack