User Instructions for the
USB-341 "ReversePipe"
USB Keyboard to Serial RS-232 Converter
Congratulations on your purchase of a VETRA USB Keyboard to Serial ASCII! This quality product is designed and built in
the USA and is backed by a VETRA Three-year Warranty and unlimited free technical support. You are welcome to
comment, please email us at [email protected] or call us at the numbers given at the end.
INTRODUCTION
The USB-341 "ReversePipe"
protocol converter changes the output of a standard USB keyboard to RS-232 format,
generating ASCII codes.
PREPARE FOR OPERATION
There are four steps to prepare the Converter for operation. Step 1 needed only to change the baud rate.
1. Baud Rate Selection: The Converter is factory pre-set to 9600 baud. Two other baud rates are available, 19,200 and
4,800 baud. To change the baud rate, open the converter, find connector P4 (located on opposite side from the USB
connector). Connect the jumper to pins 1-2 for 4,800, pins 2-3 for 9,600 (default) or 3-4 for 19,200. Baud rate selection
must be done with power-off.
2. Power the Converter: The USB-341 USB keyboard to serial ASCII Converter is powered from a +5V DC power
supply. We recommend the VIP-211 (+5Vdc @ 2 A 100 – 240 VAC 50/60 Hz) FCC & CE, which is a wall mount power
supply and may be purchased separately from Vetra; or you may provide your own supply.
3. Connect the USB Keyboard: Use the USB keyboard to connect to the USB input connector on the Converter. NOTE:
The USB keyboard may be connected to the Converter at any time. It may be disconnected and reconnected at any time.
4. Connect the RS-232 device: A Female/Female DB-9 cable is supplied with the unit to make this connection. The
supplied cable is six feet long. The Converter sends (transmits) RS-232 data on pin 3. Pin 5 of the converter is ground. The
data format output by the Converter is one stop bit, eight (8) data bits, least significant bit first, one stop bit, and no parity.
OPERATION
Translation of Keyboard Codes to ASCII Codes: Codes generated by standard USB keyboards do not correspond to
standard ASCII codes that are common with RS-232 devices. The USB-341 Converter translates keyboard codes to ASCII
codes, as shown in the TABLE below. Please note that the use of the PC keyboard Shift key is necessary to generate upper
case characters and the Shift key is necessary for certain other codes (i.e. those normally generated by using the Shift key
on the PC keyboard, for example the @ symbol is generated by Shift 2).
TOP ROW HAS MOST SIGNIFICANT HEX DIGIT – LEAST SIGNIFICANT DIGIT IS IN LEFT COLUMN
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
Space
0
@
P
`
P
F1
Num LK
Num Enter
Insert
1
!
1
A
Q
a
q
M LCNT
B LCNT
F2
Caps LK
Num /
Home
2
“
2
B
R
b
r
F3
Scr LK
Num *
End
WINAPP
3
#
3
C
S
c
s
M LALT
B LALT
F4
Num 9
Page Up
4
$
4
D
T
d
t
M RCNT
B RCNT
F5
Num 8
Page Down
5
%
5
E
U
e
u
F6
Num 7
Up Arrow
6
&
6
F
V
f
v
M RALT
B RALT
F7
Num 6
Down Arrow
7
‘
7
G
W
g
w
F8
Num 5
LFT Arrow
8
BS
(
8
H
X
h
x
M LWIN
B LWIN
F9
Num 4
RT Arrow
9
Tab
)
9
I
Y
i
y
M RWIN
B RWIN
F10
Num 3
Print Screen
A
*
:
J
Z
j
z
F11
Num 2
Pause Break
B
Esc
+
;
K
[
k
{
F12
Num 1
Delete
C
,
<
L
\
l
|
Num 0
D
Enter
-
=
M
]
m
}
Num -
E
.
>
N
^
n
~
Num +
F
/
?
O
_
o
Num .
