From 205f5e213226b7f13982036a9fb6246cfd1a4d86 Mon Sep 17 00:00:00 2001
From: Michaelangel007 <michaelangel007@sharedcraft.com>
Date: Wed, 5 Jul 2017 20:28:10 -0700
Subject: [PATCH] Optimized down to 96 bytes

---
 README.md      |  29 +++++++++++++----------------
 print_uint16   | Bin 124 -> 103 bytes
 print_uint16.s |  24 ++++++------------------
 3 files changed, 19 insertions(+), 34 deletions(-)

diff --git a/README.md b/README.md
index 0685cc6..42d0000 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Print unsigned 16-bit
 
-6502 assembly code to print an unsigned 16-bit in 117 bytes ($75).
+6502 assembly code to print an unsigned 16-bit in 96 bytes ($60).
 
 
 * No zero-page usage
@@ -13,21 +13,18 @@ Copy/Paste into your favorite emulator.
 
 ```asm
 0800:A9 12 A2 34 4C 07 08 8E
-0808:7A 08 8D 7B 08 A9 00 8D
-0810:70 08 8D 71 08 8D 72 08
-0818:A2 10 F8 0E 7A 08 2E 7B
-0820:08 A0 FD B9 73 07 79 73
-0828:07 99 73 07 C8 D0 F4 CA
-0830:D0 E9 D8 A0 04 A9 B0 8D
-0838:74 08 B9 6F 08 20 53 08
-0840:88 D0 F7 8E 70 08 B9 74
-0848:08 20 ED FD C8 CC 70 08
-0850:90 F4 60 48 20 7B F8 20
-0858:5D 08 68 29 0F D0 04 E0
-0860:00 F0 0C C9 0A 90 02 69
-0868:06 69 B0 9D 74 08 E8 60
-0870:00 00 00 00 00 00 00 00
-0878:00 00 00 00 
+0808:65 08 8D 66 08 A9 00 8D
+0810:61 08 8D 62 08 8D 63 08
+0818:A2 10 F8 0E 65 08 2E 66
+0820:08 A0 FD B9 64 07 79 64
+0828:07 99 64 07 C8 D0 F4 CA
+0830:D0 E9 D8 A0 03 B9 60 08
+0838:20 44 08 88 D0 F7 8A E0
+0840:00 F0 11 60 48 20 7B F8
+0848:20 4E 08 68 29 0F D0 04
+0850:E0 00 F0 0C C9 0A 90 02
+0858:69 06 69 B0 20 ED FD E8
+0860:60 00 00 00 00 00 00 
 ```
 
 
diff --git a/print_uint16 b/print_uint16
index 44bf318495dcd4818c28dcbd2d0373d4cb4e344b..8415f2f7af51fe6ed3cb6990ca5ebc56fa867edb 100644
GIT binary patch
literal 103
zcmZ1}w8+GVoue<6qc@FXB|~o_M{g2GZ!*UsfggOS9C~RS3;ym*VXsVKpP9mb;=-3x
z7hc|2z`QeoL&1fk<HGl@2Miws6Fd~Ee<=8IWN7kVU;zs7oaCCol*yL4LE-J+7YPht
F0012$C+q+K

literal 124
zcmZ1}w8+GVoujXcqqmx4B|~okM{glVZxP2LfggNT9D3Cp3;ymbX0I$}pIOX);=-3x
z7hc|2z_M~fZwbfFd=7<Rj*bi8`wBRAmT)M%{d?j}0mp<d2_6d7KNMm)GBo)wusmS+
Wz;lvo0#hbi=7zZ?94`_WkN^N~S1+Rg

diff --git a/print_uint16.s b/print_uint16.s
index f0b27b8..a3e17f7 100644
--- a/print_uint16.s
+++ b/print_uint16.s
@@ -45,25 +45,17 @@ _DoubleDabble           ;              Y=FD   Y=FE   Y=FF   Y=00
         CLD             ; X=0 = output length
 
 DecWidth
-        LDY #4          ; 6 digit output for special case of $0000
-
-        LDA #'0' + $80  ; handle special case input = $0000
-        STA _output     ; since we always print at least 1 digit
-
+        LDY #3          ; maximum 6 digits output
 BCD2Chars
         LDA _bcd-1,Y
-        JSR HexA        ; _output[0..7] = '?'
+        JSR HexA        ; print 0, 1, or 2 hex digits
         DEY
         BNE BCD2Chars
 
-        STX _len        ; output buffer len = num digits to print
+        TXA
+        CPX #0          ; Handle special case input = $0000 of no output
+        BEQ  _HaveLeadingDigit
 
-OutDigits
-        LDA _output,Y   ; always print digit in "ones" place
-        JSR COUT
-        INY
-        CPY _len
-        BCC OutDigits
 _PrintDone
         RTS
 
@@ -83,20 +75,16 @@ _HexNib
 
 _HaveLeadingDigit
         CMP #$A         ; n < 10 ?
-
         BCC _Hex2Asc
         ADC #6          ; n += 6    $A -> +6 + (C=1) = $11
 _Hex2Asc
         ADC #'0' + $80  ; inverse=remove #$80
 PutChar
-        STA _output,X
+        JSR COUT
         INX             ; X = output string length
 _HexAsciiDone
         RTS
 
-
 _bcd    ds  4   ; 6 chars for printing dec
-_len    = _bcd  ; alias
-_output ds  6   ; BCD -> 6 chars
 _temp   db  0,0