diff --git a/README.md b/README.md
index 1c197fe..ff7f714 100644
--- a/README.md
+++ b/README.md
@@ -28,9 +28,6 @@ go install https://github.com/nonoo/kappanhang
 - Make sure network settings (on the Icom IC-705 in: `Menu -> Set ->
   WLAN set -> Remote settings`) are the following:
   - **Network control** is turned on.
-  - **Network user 1** username is `beer` and the password is `beerbeer`.
-    These are fixed as the password encoding of the RS-BA1 protocol has not
-    been decrypted yet. See [passcode.txt](passcode.txt) for more information.
   - **UDP ports** are on their default values:
     - Control port: `50001`
     - Serial port: `50002`
@@ -48,7 +45,9 @@ You can get the available command line parameters with the `-h` command line
 argument.
 
 If no command line arguments are set, then the app will try to connect to the
-host **ic-705** (ic-705.local or ic-705.localdomain).
+host **ic-705** (ic-705.local or ic-705.localdomain) with the username `beer`
+and password `beerbeer`. You can set the username with the `-u` and the
+password with the `-p` command line arguments.
 
 After it is connected and logged in:
 
diff --git a/args.go b/args.go
index 3a5f328..4846c66 100644
--- a/args.go
+++ b/args.go
@@ -10,6 +10,8 @@ import (
 
 var verboseLog bool
 var connectAddress string
+var username string
+var password string
 var serialTCPPort uint16
 var enableSerialDevice bool
 var rigctldModel uint
@@ -22,6 +24,8 @@ func parseArgs() {
 	h := getopt.BoolLong("help", 'h', "display help")
 	v := getopt.BoolLong("verbose", 'v', "Enable verbose (debug) logging")
 	a := getopt.StringLong("address", 'a', "IC-705", "Connect to address")
+	u := getopt.StringLong("username", 'u', "beer", "Username")
+	p := getopt.StringLong("password", 'p', "beerbeer", "Password")
 	t := getopt.Uint16Long("serial-tcp-port", 't', 4533, "Expose radio's serial port on this TCP port")
 	s := getopt.BoolLong("enable-serial-device", 's', "Expose radio's serial port as a virtual serial port")
 	m := getopt.UintLong("rigctld-model", 'm', 3085, "rigctld model number")
@@ -40,6 +44,8 @@ func parseArgs() {
 
 	verboseLog = *v
 	connectAddress = *a
+	username = *u
+	password = *p
 	serialTCPPort = *t
 	enableSerialDevice = *s
 	rigctldModel = *m
diff --git a/controlstream.go b/controlstream.go
index 1ac8452..8a6fbf5 100644
--- a/controlstream.go
+++ b/controlstream.go
@@ -43,6 +43,8 @@ func (s *controlStream) sendPktLogin() error {
 	if _, err := rand.Read(authStartID[:]); err != nil {
 		return err
 	}
+	usernameEncoded := passcode(username)
+	passwordEncoded := passcode(password)
 	p := []byte{0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		byte(s.common.localSID >> 24), byte(s.common.localSID >> 16), byte(s.common.localSID >> 8), byte(s.common.localSID),
 		byte(s.common.remoteSID >> 24), byte(s.common.remoteSID >> 16), byte(s.common.remoteSID >> 8), byte(s.common.remoteSID),
@@ -52,10 +54,14 @@ func (s *controlStream) sendPktLogin() error {
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-		0x2b, 0x3f, 0x55, 0x5c, 0x00, 0x00, 0x00, 0x00, // username: beer
-		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-		0x2b, 0x3f, 0x55, 0x5c, 0x3f, 0x25, 0x77, 0x58, // pass: beerbeer
-		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		usernameEncoded[0], usernameEncoded[1], usernameEncoded[2], usernameEncoded[3],
+		usernameEncoded[4], usernameEncoded[5], usernameEncoded[6], usernameEncoded[7],
+		usernameEncoded[8], usernameEncoded[9], usernameEncoded[10], usernameEncoded[11],
+		usernameEncoded[12], usernameEncoded[13], usernameEncoded[14], usernameEncoded[15],
+		passwordEncoded[0], passwordEncoded[1], passwordEncoded[2], passwordEncoded[3],
+		passwordEncoded[4], passwordEncoded[5], passwordEncoded[6], passwordEncoded[7],
+		passwordEncoded[8], passwordEncoded[9], passwordEncoded[10], passwordEncoded[11],
+		passwordEncoded[12], passwordEncoded[13], passwordEncoded[14], passwordEncoded[15],
 		0x69, 0x63, 0x6f, 0x6d, 0x2d, 0x70, 0x63, 0x00, // icom-pc in plain text
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -107,6 +113,7 @@ func (s *controlStream) sendRequestSerialAndAudio() error {
 
 	txSeqBufLengthMs := uint16(txSeqBufLength.Milliseconds())
 
+	usernameEncoded := passcode(username)
 	p := []byte{0x90, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		byte(s.common.localSID >> 24), byte(s.common.localSID >> 16), byte(s.common.localSID >> 8), byte(s.common.localSID),
 		byte(s.common.remoteSID >> 24), byte(s.common.remoteSID >> 16), byte(s.common.remoteSID >> 8), byte(s.common.remoteSID),
@@ -120,8 +127,10 @@ func (s *controlStream) sendRequestSerialAndAudio() error {
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-		0x2b, 0x3f, 0x55, 0x5c, 0x00, 0x00, 0x00, 0x00, // username: beer
-		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		usernameEncoded[0], usernameEncoded[1], usernameEncoded[2], usernameEncoded[3],
+		usernameEncoded[4], usernameEncoded[5], usernameEncoded[6], usernameEncoded[7],
+		usernameEncoded[8], usernameEncoded[9], usernameEncoded[10], usernameEncoded[11],
+		usernameEncoded[12], usernameEncoded[13], usernameEncoded[14], usernameEncoded[15],
 		0x01, 0x01, 0x04, 0x04, 0x00, 0x00, byte(audioSampleRate >> 8), byte(audioSampleRate & 0xff),
 		0x00, 0x00, byte(audioSampleRate >> 8), byte(audioSampleRate & 0xff),
 		0x00, 0x00, byte(serialStreamPort >> 8), byte(serialStreamPort & 0xff),
@@ -341,7 +350,7 @@ func (s *controlStream) init() error {
 		return err
 	}
 	if bytes.Equal(r[48:52], []byte{0xff, 0xff, 0xff, 0xfe}) {
-		return errors.New("invalid user/password")
+		return errors.New("invalid username/password")
 	}
 
 	s.common.pkt7.startPeriodicSend(&s.common, 2, false)
diff --git a/main.go b/main.go
index 23ada92..1f97dca 100644
--- a/main.go
+++ b/main.go
@@ -58,6 +58,9 @@ func runControlStream(osSignal chan os.Signal) (requireWait, shouldExit bool, ex
 	if err := ctrl.init(); err != nil {
 		log.Error(err)
 		ctrl.deinit()
+		if strings.Contains(err.Error(), "invalid username/password") {
+			return false, true, 1
+		}
 		return
 	}
 
diff --git a/passcode.go b/passcode.go
new file mode 100644
index 0000000..5096cbd
--- /dev/null
+++ b/passcode.go
@@ -0,0 +1,107 @@
+package main
+
+var sequence = map[int]byte{
+	32:  0x47,
+	33:  0x5d,
+	34:  0x4c,
+	35:  0x42,
+	36:  0x66,
+	37:  0x20,
+	38:  0x23,
+	39:  0x46,
+	40:  0x4e,
+	41:  0x57,
+	42:  0x45,
+	43:  0x3d,
+	44:  0x67,
+	45:  0x76,
+	46:  0x60,
+	47:  0x41,
+	48:  0x62,
+	49:  0x39,
+	50:  0x59,
+	51:  0x2d,
+	52:  0x68,
+	53:  0x7e,
+	54:  0x7c,
+	55:  0x65,
+	56:  0x7d,
+	57:  0x49,
+	58:  0x29,
+	59:  0x72,
+	60:  0x73,
+	61:  0x78,
+	62:  0x21,
+	63:  0x6e,
+	64:  0x5a,
+	65:  0x5e,
+	66:  0x4a,
+	67:  0x3e,
+	68:  0x71,
+	69:  0x2c,
+	70:  0x2a,
+	71:  0x54,
+	72:  0x3c,
+	73:  0x3a,
+	74:  0x63,
+	75:  0x4f,
+	76:  0x43,
+	77:  0x75,
+	78:  0x27,
+	79:  0x79,
+	80:  0x5b,
+	81:  0x35,
+	82:  0x70,
+	83:  0x48,
+	84:  0x6b,
+	85:  0x56,
+	86:  0x6f,
+	87:  0x34,
+	88:  0x32,
+	89:  0x6c,
+	90:  0x30,
+	91:  0x61,
+	92:  0x6d,
+	93:  0x7b,
+	94:  0x2f,
+	95:  0x4b,
+	96:  0x64,
+	97:  0x38,
+	98:  0x2b,
+	99:  0x2e,
+	100: 0x50,
+	101: 0x40,
+	102: 0x3f,
+	103: 0x55,
+	104: 0x33,
+	105: 0x37,
+	106: 0x25,
+	107: 0x77,
+	108: 0x24,
+	109: 0x26,
+	110: 0x74,
+	111: 0x6a,
+	112: 0x28,
+	113: 0x53,
+	114: 0x4d,
+	115: 0x69,
+	116: 0x22,
+	117: 0x5c,
+	118: 0x44,
+	119: 0x31,
+	120: 0x36,
+	121: 0x58,
+	122: 0x3b,
+	123: 0x7a,
+	124: 0x51,
+	125: 0x5f,
+	126: 0x52,
+}
+
+func passcode(s string) (res []byte) {
+	res = make([]byte, 16)
+	for i := 0; i < len(s) && i < len(res); i++ {
+		res[i] = sequence[int(s[i])+i]
+	}
+	return res
+}
diff --git a/passcode.txt b/passcode.txt
deleted file mode 100644
index 990b6d3..0000000
--- a/passcode.txt
+++ /dev/null
@@ -1,101 +0,0 @@
-The following coding is used by the Icom software for encoding usernames and
-passwords in login packets. Columns are: ASCII decimal, character, encoded
-character. This listing is only valid for the first character. Subsequent
-characters are encoded to different values, and the algorithm is currently
-unknown.
-
-32  space 0x47
-33  !     0x5d
-34  "     0x4c
-35  #     0x42
-36  $     0x66
-37  %     0x20
-38  &     0x23
-39  '     0x46
-40  (     0x4e
-41  )     0x57
-42  *     0x45
-43  +     0x3d
-44  ,     0x67
-45  -     0x76
-46  .     0x60
-47  /     0x41
-48  0     0x62
-49  1     0x39
-50  2     0x59
-51  3     0x2d
-52  4     0x68
-53  5     0x7e
-54  6     0x7c
-55  7     0x65
-56  8     0x7d
-57  9     0x49
-58  :     0x29
-59  ;     0x72
-60  <     0x73
-61  =     0x78
-62  >     0x21
-63  ?     0x6e
-64  @     0x5a
-65  A     0x5e
-66  B     0x4a
-67  C     0x3e
-68  D     0x71
-69  E     0x2c
-70  F     0x2a
-71  G     0x54
-72  H     0x3c
-73  I     0x3a
-74  J     0x63
-75  K     0x4f
-76  L     0x43
-77  M     0x75
-78  N     0x27
-79  O     0x79
-80  P     0x5b
-81  Q     0x35
-82  R     0x70
-83  S     0x48
-84  T     0x6b
-85  U     0x56
-86  V     0x6f
-87  W     0x34
-88  X     0x32
-89  Y     0x6c
-90  Z     0x30
-91  [     0x61
-92  \     0x6d
-93  ]     0x7b
-94  ^     0x2f
-95  _     0x4b
-96  `     0x64
-97  a     0x38
-98  b     0x2b
-99  c     0x2e
-100 d     0x50
-101 e     0x40
-102 f     0x3f
-103 g     0x55
-104 h     0x33
-105 i     0x37
-106 j     0x25
-107 k     0x77
-108 l     0x24
-109 m     0x26
-110 n     0x74
-111 o     0x6a
-112 p     0x28
-113 q     0x53
-114 r     0x4d
-115 s     0x69
-116 t     0x22
-117 u     0x5c
-118 v     0x44
-119 w     0x31
-120 x     0x36
-121 y     0x58
-122 z     0x3b
-123 {     0x7a
-124 |     0x51
-125 }     0x5f
-126 ~     0x52
diff --git a/pkt0.go b/pkt0.go
index 6fd898a..c9aa4ff 100644
--- a/pkt0.go
+++ b/pkt0.go
@@ -36,7 +36,7 @@ func (p *pkt0Type) retransmitRange(s *streamCommon, start, end uint16) error {
 				return err
 			}
 		} else {
-			log.Debug(s.name+"/can't retransmit #", start, " - not found")
+			log.Debug(s.name+"/can't retransmit #", start, " - not found ")
 
 			// Sending an idle with the requested seqnum.
 			if err := p.sendIdle(s, false, start); err != nil {