From 58b9c37bf4479c436e3477e1753e48527276a595 Mon Sep 17 00:00:00 2001
From: Phil Hagelberg <phil@hagelb.org>
Date: Mon, 1 Jul 2019 19:59:42 -0700
Subject: [PATCH] Scan all the things. 6kro but no modifiers.

---
 README.md    |  2 +-
 keycodes.scm | 16 ++++-------
 menelaus.scm | 78 ++++++++++++++++++++++++++++++++++++++++------------
 3 files changed, 66 insertions(+), 30 deletions(-)

diff --git a/README.md b/README.md
index c997a9d..2870c95 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,6 @@ for Teensy models will be added later.
 
 ## License
 
-Copyright © 2014 Phil Hagelberg and contributors
+Copyright © 2014-2019 Phil Hagelberg and contributors
 
 Released under the [GNU GPL version 3](https://www.gnu.org/licenses/gpl.html).
diff --git a/keycodes.scm b/keycodes.scm
index c461fa2..7b70f9e 100644
--- a/keycodes.scm
+++ b/keycodes.scm
@@ -40,14 +40,8 @@
 (define key-tab 43)
 (define key-enter 40)
 
-(define mod-ctrl 0)
-(define mod-shift 0)
-(define mod-alt 0)
-(define mod-gui 0)
-(define mod-fn 0)
-
-;; (define mod-ctrl #x01)
-;; (define mod-shift #x02)
-;; (define mod-alt #x04)
-;; (define mod-gui #x08)
-;; (define mod-fn #x16)
+(define mod-ctrl #x01)
+(define mod-shift #x02)
+(define mod-alt #x04)
+(define mod-gui #x08)
+(define mod-fn #x16)
diff --git a/menelaus.scm b/menelaus.scm
index ac5caf1..d656907 100644
--- a/menelaus.scm
+++ b/menelaus.scm
@@ -4,29 +4,71 @@
 (define rows (list 0 1 2 3))
 (define row-pins (vector 3 2 1 0))
 (define columns (list 0 1 2 3 4 5 6 7 8 9 10))
-(define column-pins (vector 11 12 18 19 10 4 7 8 9 5 6))
+(define column-pins (vector 6 5 9 8 7 4 10 19 18 12 11))
 
-(for-each-vector output row-pins)
-(for-each-vector high row-pins)
-(for-each-vector input column-pins)
-(for-each-vector high column-pins) ; activate pullup resistors
+(define max-keys 6)
 
-(call-c-func "usb_init")
-(pause 200)
-
-(define (scan-column last offset)
-  (if (low? (vector-ref column-pins (mod offset 11)))
-      (vector-ref layout offset)
-      last))
-
-(define (scan-row last row)
+(define (init)
+  (for-each-vector output row-pins)
   (for-each-vector high row-pins)
-  (low (vector-ref row-pins row))
-  (fold scan-column last (map (lambda (col) (+ col (* row 11))) columns)))
+  (for-each-vector input column-pins)
+  (for-each-vector high column-pins) ; activate pullup resistors
+
+  (call-c-func "usb_init")
+  (pause 200))
+
+(define (offset-for row col)
+  (+ col (* row (length columns))))
+
+(define (usb-send modifiers key1 key2 key3 key4 key5 key6)
+  (call-c-func "usb_send" modifiers key1 key2 key3 key4 key5 key6))
+
+(define (scan-key keys-pressed key-count row col)
+  ;; pullup resistors mean a closed circuit is low rather than high
+  (if (low? (vector-ref column-pins col))
+      (begin
+        (if (<= key-count max-keys)
+            (vector-set! keys-pressed key-count (offset-for row col))
+            #f)
+        (+ key-count 1))
+      key-count))
+
+(define (scan-column keys-pressed key-count row columns-left)
+  (if (= (length columns-left) 0)
+      key-count
+      (let ((key-count (scan-key keys-pressed key-count row (car columns-left))))
+        (scan-column keys-pressed key-count row (cdr columns-left)))))
+
+(define (activate-row row)
+  (for-each-vector high row-pins)
+  (low (vector-ref row-pins row)))
+
+(define (scan-matrix keys-pressed key-count rows-left)
+  (if (= (length rows-left) 0)
+      key-count
+      (let ((_ (activate-row (car rows-left)))
+            (key-count (scan-column keys-pressed key-count
+                                    (car rows-left) columns)))
+        (scan-matrix keys-pressed key-count (cdr rows-left)))))
+
+(define (layout-lookup key-position)
+  (vector-ref layout key-position))
+
+(define (keycodes-for keys-pressed key-count keycodes)
+  (if (= 0 key-count)
+      (vector->list keycodes)
+      (let ((keycode (vector-ref layout (vector-ref keys-pressed key-count))))
+        ;; (printf "keycode ~s ~s~n" keycode key-count)
+        (vector-set! keycodes key-count keycode)
+        (keycodes-for keys-pressed (- key-count 1) keycodes))))
 
 (define (loop)
-  (let ((pressed (free! (fold scan-row 0 rows))))
-    (call-c-func "usb_send" 0 pressed 0 0 0 0 0))
+  (free! (let ((keys-pressed (vector 0 0 0 0 0 0 0)))
+           (let ((key-count (scan-matrix keys-pressed 1 rows)))
+             (apply usb-send (keycodes-for keys-pressed (- key-count 1)
+                                           (vector 0 0 0 0 0 0 0))))))
   (loop))
 
+;;; showtime!
+(init)
 (loop)