whoops nums bitwised

src/device/output/key/char.go

@@ -57,7 +57,7 @@ func ToChar(k Key) byte {
 }
 
 func FromChar(b byte) Key {
-	if b < 'a' {
+	if 'A' <= b && b <= 'Z' {
 		b += 'a' - 'A'
 	}
 	v, ok := charToKey[b]

src/device/output/key/char_test.go

@@ -3,6 +3,9 @@ package key
 import "testing"
 
 func TestFromChar(t *testing.T) {
+	if got := FromChar('1'); got != N1 {
+		t.Error(got)
+	}
 	if got := FromChar('a'); got != A {
 		t.Error(got)
 	}