diff --git a/ACME_Lib/6502/rc4.a b/ACME_Lib/6502/rc4.a
index 1a73150..9d62811 100644
--- a/ACME_Lib/6502/rc4.a
+++ b/ACME_Lib/6502/rc4.a
@@ -1,22 +1,22 @@
 ;ACME 0.97
 
 ; this is an implementation of the stream cipher algorithm known as RC4.
-; UNFINISHED - DO NOT USE!
 
 ; you need to define these symbols in your code:
 ;	rc4_length	a single byte to hold key/chunk lengths
-;	rc4_count	a single byte (iteration counter)
+;	rc4_count	a single byte (tmp var for iteration counter)
 ;	rc4_ii		a single byte to hold state
 ;	rc4_jj		a single byte to hold state
 ;	rc4_state	a full page of memory (256 bytes)
+;	rc4_key		key buffer
 ;	rc4_in		input buffer
 ;	rc4_out		output buffer
 ; the size of the buffers limits how much data you can pass to the functions.
-; the two buffer addresses may be identical, in that case the output will
-; overwrite the input.
+; all three buffer addresses may be identical, in that case the output will
+; overwrite the input (and/or the key).
 ; functions you can then call:
 ;	rc4_init	initialise state
-;	rc4_key_X	use key (in input buffer, length in X) to change state
+;	rc4_usekey_X	use key (in key buffer, length in X) to change state
 ;	rc4_reset	reset ii and jj (call between keying and processing)
 ;	rc4_process_X	de/encrypt a chunk of data buffer-to-buffer (length in X)
 
@@ -27,6 +27,7 @@
 	.ii	= rc4_ii
 	.jj	= rc4_jj
 	.state	= rc4_state
+	.keybuf	= rc4_key
 	.inbuf	= rc4_in
 	.outbuf	= rc4_out
 
@@ -44,8 +45,9 @@ rc4_reset	ldx #0
 		stx .jj
 		rts
 
-; use key (in input buffer, length in X) to change permutation in state array
-rc4_key_X
+; use key (in key buffer, length in X) to change permutation in state array
+; X==0 means 256!
+rc4_usekey_X
 ; X holds .ii (but we count from 0 to 255 and so do not use the real .ii at all)
 ; Y holds .jj or .count (.jj is then in A)
 		stx .length
@@ -61,7 +63,7 @@ rc4_key_X
 			adc .state, x
 			ldy .count
 			clc
-			adc .inbuf, y
+			adc .keybuf, y
 			;sta .jj
 						;if (++count == length)
 						;	count = 0;