From: Tobias Girstmair <tobi@isticktoit.net>
Date: Thu, 4 Mar 2021 12:27:09 +0000 (+0100)
Subject: new version
X-Git-Url: https://git.gir.st/Chiptunes-pms150c.git/commitdiff_plain/2ae98f0b3db825606a7ecfdb4cf3e9ea6c6dbbce

new version

div6 was prototyped with this program:

typedef unsigned char u8;
int main(void) {
	for (int i = 0; i <= 0x78; i++) {
		u8 real = i/6;
		u8 test = i;

		test >>= 1;
		test += i;

		test >>= 1;
		test += 0;

		test >>= 1;
		test += i;

		test >>= 1;
		test += 0;

		test >>= 1;
		test += i;

		test >>= 1;
		test += 0;

		test >>= 1;
		test >>= 1;

		if (test != real)
			printf ("%hhd/6 == %hhd != %hhd\n", i, real, test);
	}
	return 0;
}
---

diff --git a/bsv.c b/bsv.c
index 8109501..8ce4b42 100644
--- a/bsv.c
+++ b/bsv.c
@@ -70,31 +70,18 @@ void main(void){
 		MOV	(tmp_1, acc) // acc saved in tmp_1; fresh acc
 		MOV	(acc, i2)
 		// shift-divide by six
-		// note: i2 is max 0x78; so acc will <= 20.
-
+		// note: i2 is max 0x78; so acc will <= 20. (breaks vor values >=128)
                 SR	(acc)
 		ADD	(acc, i2)
-
 		SR	(acc)
-                //ADD acc, 0
-
                 SR	(acc)
 		ADD	(acc, i2)
-
 		SR	(acc)
-                //ADD acc, 0
-
                 SR	(acc)
 		ADD	(acc, i2)
-
 		SR	(acc)
-                //ADD acc, 0
-
 		SR	(acc)
-                //ADD acc, 0
 		SR	(acc)
-                //ADD acc, 0
-
 		// end divide by six
 		AND	(acc, tmp_1) // acc restored from tmp_1
 		AND	(acc, 3)