/
KeyspanUSB.shtml
196 lines (158 loc) · 7.33 KB
/
KeyspanUSB.shtml
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta name="generator" content=
"HTML Tidy for Mac OS X (vers 31 October 2006 - Apple Inc. build 15.17), see www.w3.org">
<title>JMRI Hardware Support - Keyspan USB adapter</title>
<meta name="author" content="Bob Jacobsen">
<meta name="author" content="John Plocher">
<meta name="keywords" content=
"Keyspan USB java model railroad JMRI install">
<!-- Style -->
<meta http-equiv="Content-Type" content=
"text/html; charset=us-ascii">
<link rel="stylesheet" type="text/css" href="/css/default.css"
media="screen">
<link rel="stylesheet" type="text/css" href="/css/print.css"
media="print">
<link rel="icon" href="/images/jmri.ico" type="image/png">
<link rel="home" title="Home" href="/">
<!-- /Style -->
</head>
<body>
<!--#include virtual="/Header.shtml" -->
<div id="mBody">
<!--#include virtual="Sidebar.shtml" -->
<div id="mainContent">
<h1>Hardware Support: Keyspan USB connections</h1>
<p>This page describes tests of two USB-to-serial adapters,
done circa 2010 using the <a href="MS100.shtml">Digitrax
MS100</a> LocoNet® interface.</p>
<p class="important">We strongly recommend to use a
better solution to connect a computer to a LocoNet,
such as the <a href="LocoBufferUSB.shtml">LocoBuffer
USB</a> or the <a href="PR3.shtml">Digitrax PR3</a>/<a
href="PR4.shtml">PR4</a>.</p>
<p>The MS100 is a passive level shifter that gets its power
from the control leads in the RS232 interface. Digitrax has
not published a schematic, but Bill Robinson of Team Digital
has graciously provided a schematic of their level shifter
which is thought to be very similar.</p>
<p><img src="./images/LN_to_PC.gif" alt=
"Sample LocoNet to RS232 Interface Schematic"></p>
<h2>Summary</h2>
<dl>
<dt class="left">Keyspan PDA adapter P/N USA-19</dt>
<dt class="left">Summary: This worked fine.</dt>
<dd>
<p>Unfortunately, this adapter is no longer made. We
believe that the replacement "Keyspan High Speed Serial
Adapter" Part# USA-19QW is the same unit.</p>
<p>We've had a report that this PDA adapter can't work
with a LocoBuffer at 57,600 baud. There seem to be
multiple versions of the adapter, with slightly different
model numbers, and it could be that some of them will
only work at speeds of up to 56,000 baud.</p>
</dd>
<dt class="left">Keyspan Dual Serial Adapter P/N
USA-28X</dt>
<dt class="left">Summary: This did not work.</dt>
<dd>Problems: the USB adapter provides only one control
line output, and the serial port outputs were only +/- 5V.
This was not enough to power the MS100 during receive.</dd>
</dl>
<h2>Details</h2>
<dl>
<dt class="left">Keyspan PDA adapter P/N USA-19</dt>
<dt class="left">Summary: This worked fine.</dt>
<dd>
<p>This was actually the second USB serial adapter I
tried, after the Keyspan Dual Serial Adapter (see below).
This adapter provides a DB9 male plug, pinout available
from the <a href=
"http://www.keyspan.com/products/USB/PDAadapter/docs/mac/html/homepage29.html">
Keyspan product support page</a>. Note that there are
both RTS and DTR outputs; these can be separately
controlled to provide + and - voltage to the MS100.</p>
<p>I connected it through a DB9 female to DB25 male
adapter cable that I happened to have, and the test
program was immediately able to communicate with the
LocoNet.</p>
<h3>DB9 female to DB25 male connections</h3>
<pre>
DB9 pin DB25 pin
------- --------
DCD 1 8
RxD 2 3
TxD 3 2
DTR 4 20
ground 5 7
DSR 6 6
RTS 7 4
CTS 8 5
RI 9 22
</pre>
<p>Note that I didn't test the level input from the MS100
(DSR, CTS).</p>
</dd>
<dt class="left">Keyspan Dual Serial Adapter P/N
USA-28X</dt>
<dt class="left">Summary: This did not work.</dt>
<dd>
<p>The initial problem was that the USB adapter provides
only one control line output (see pinout on the <a href=
"http://www.keyspan.com/products/USB/usa28x/docs/swp/aPinOuts.html">
Keyspan product support page</a>. This means that the
serial port can only provide one of the two + and -
levels needed for the MS100. Since there are two ports, I
build a small adapter to use the control line from the
second port to provide the other level.</p>
<p><a href="./images/KeyspanJumper.jpg"><img src=
"./images/KeyspanJumper-thumb.jpg" alt=
"Keyspan USA-28X did not function">(click to
enlarge)</a></p>
<p>The second problem was that the serial port outputs
were only +/- 5V. This was not enough to power the MS100
during receive.</p>
<p>The following picture shows the transmit data levels
from the Keyspan adapter. DC levels had similar ranges.
This was a large enough swing to drive the LocoNet
itself, but not to power the receive level shifter in the
MS100.</p>
<p><a href="./images/KeyspanTxD.jpg"><img src=
"./images/KeyspanTxD-thumb.jpg" alt=
"Oscilloscope image showing Keyspan USA-28X TxD voltages">
(click to enlarge)</a></p>
<p>Providing auxiliary +/- 9V power to the MS100, without
using the output lines as a power source, was not
sufficient. The following picture is the received data,
nominally an RS232 signal of at least +/-6 volts, from
the MS100. The received data signal was getting up to 6V,
marginally OK, but it was not going below ground. The USB
serial adapter was not reporting any received characters
to the Macintosh.</p>
<p><a href="./images/KeyspanRxD.jpg"><img src=
"./images/KeyspanRxD-thumb.jpg" alt=
"Oscilloscope image showing inadequate Keyspan USA-28X RxD voltages">
(click to enlarge)</a></p>
<h3>Hardware & Software used</h3>
<p>The tests were done with a PowerBook G4 400MHz, Mac OS
9.1. The test program was a Java application created with
CodeWarrior 4.1.0.3 build 661. This program is available
on request, see below for address. Java access to the USB
serial adapters was via Patrick Beard's Macintosh
implementation of javax.comm.</p>
<p>The Digitrax system was a Chief, DT100IR throttle, and
various decoders on the layout. Traffic from command
station, throttle and various auxiliary components (PM4,
DS54) was available for testing.</p>
</dd>
</dl>
<p>LocoNet® is a registered trademark of <a href=
"http://www.digitrax.com">Digitrax, Inc.</a></p>
<!--#include virtual="/Footer.shtml" -->
</div><!-- closes #mainContent-->
</div><!-- closes #mBody-->
</body>
</html>