CHD Elektroservis 8-440 User manual

7
Model 8-440 / 8-441
ver. 1.0
USER MANUAL
© 2015 CHD Elektroservis

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
2
Content
page
1. Device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Function of interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Connection to MIDI system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Standard working mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. M
emory bank bulk transfer / back-up and communication
. . . . . . . . . . . . . . . . . 4
3. Interface operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Initialization sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. Instrument control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.3. Working status indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. System parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.1.1. MIDI Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.1.2. Default Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.1.3. Autoreset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2. Preset parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2.1. Key Shift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.2.2. Chnl Aftertouch Amount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.2.3. Pitch Bend Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2.4. Indicator Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5. MIDI implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.1. Channel commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.1.1. Note On/Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1.2. Control Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1.2.1. Standard controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1.2.2. Controllers for preset parameters setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1.2.3. Controllers for interface’s functions control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.3. Channel Aftertouch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1.4. Pitch Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.1.5. Program Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2. Common system command - Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.3. System exclusive messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6. Possible limitation during the interface usage
and recommended settings . . . . . . . . . . 16
7. Technical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8. Warranty conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Appendices
A. MIDI implementation chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
B. Error status indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
C. Factory Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
D. Loop in MIDI communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
E. Automatic activation of interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
This manual in PDF form is available on supplemental CD-ROM or on manufacturer’s web-pages.
Manufacturer :
CHD Elektroservis
Nad kundratkou 27, 19000 Praha 9
Czech Republic
[e-mail]
www.chd-el.cz

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
3
1. DEVICE DESCRIPTION
VP330-KBD / RS505-KBD is a MIDI retrofit for Roland VP-330 / RS-505 instruments. It is
designed for installation inside the instrument. The device enables the instrument to be controlled via
MIDI Notes and commands as a MIDI expander. However, all original features of VP-330 / RS-505
instruments remain unchanged after the interface installation. If the interface is switched off or if it isn’t
connected to MIDI system, the instrument works exactly the same way as before the interface
installation.
1.1. FUNCTION OF INTERFACE
Pic. 1a – VP330-KBD - Functional block schematics
Functional block schematics
of the interface is shown on pic. 1.
The interface polyphonically
controls VP-330’s keyboard
(pic.1a). If installed in RS-505, the
interface controls instrument’s
keyboard in the same polyphonic
way and simultaneously the
monophonic bass section (pic. 1b).
The interface can control detuning
of main oscillator in both VP-330
and RS-505 – PITCH SHIFT
function of the instruments.
The interface controls the
instrument via MIDI Notes, CC and
other commands. Next chapters
describe the enhanced functions of
the MIDI interface in detail.
Pic. 1b – RS505-KBD - Functional block schematics

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
4
2. CONNECTION TO MIDI SYSTEM
The interface has connectors for both MIDI data input and output. For interconnection, use
standard MIDI cables with DIN 41524 connector (5-pin / 180°).
2.1. STANDARD WORKING MODE
If the interface is switched on and active (see chapter 3.2), all incoming MIDI data (from
sequencer, master keyboard, etc.) at MIDI input of the interface are transferred to MIDI-THRU/OUT
output of the interface remaining unchanged (THRU function). Another MIDI devices might be chained
to master / host system without an additional Thru-Box etc. - MIDI input of the next chained MIDI
device will be simply interconnected with MIDI-THRU/OUT output of the interface (see pic. 2).
If there are no other devices to be chained and controlled from the MIDI master / host system,
only MIDI-IN cable is necessary (from master / host system to MIDI-IN input of the interface). MIDI-
THRU/OUT output of the interface remain unconnected.
Pic. 2 – Connection to MIDI system for standard working mode
2.2. MEMORY BANK BULK TRANSFER / BACK-UP AND COMMUNICATION
Interface’s own System Exclusive messages (Memory bank content, status data, etc.) can be
transmitted via MIDI-THRU/OUT output as well. In this case MIDI output MIDI-THRU/OUT must be
connected to MIDI input of the master host system (PC, sequencer…) recording / backing-up the data
from interface’s memory as well as other device specific MIDI messages (see pic. 3).
Pic. 3 – Connection to MIDI system for memory bank content or status data transfer
Attention! In this case the MIDI ECHO or THRU function of the recording sequencer has to be
disabled (see appendix D). Otherwise MIDI communication loop can occur and “freeze” the MIDI
system!

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
5
3. INTERFACE OPERATION
The interface itself has only one manual control element – tumbler switch. It switches the
interface on (activation of the interface) or off (deactivation of the interface). Working status and
functions of the interface are indicated by bi-color (red / green) LED.
Remark: It is not necessary to install the switch and indication LED. The interface can be
switched on and off remotely – by MIDI commands. For details see Appendix E.
3.1. INITIALIZATION SEQUENCE
When the instrument is switched on, the interface reset sequence is executed automatically.
During this sequence, system and default preset settings are transferred from internal memory banks
to edit buffers (see pic. 4 - [5], [6]). After the initial sequence, the interface checks the status of the
tumbler switch.
3.2. INSTRUMENT CONTROL
If the interface is switched “off”, it has no effect on VP-330 / RS-505. Both instruments work the
same way as there is no MIDI interface installed. In “off” status of the interface, all MIDI communication
is disabled and the indication LED doesn’t light.
After switching on the interface (by manual switch), it stays inactive awaiting the first MIDI note
or other MIDI command.
When the first acceptable MIDI note, controller or other event is received, the indication LED
turns red and the MIDI control of the instrument is activated (see pic. 4 - [9], [10]) accordingly to the
actual stored interface settings (see chapter 4). All controllers on VP-330 / RS-505 instrument’s panel
(sliders, switches) remain fully functional.
3.3. WORKING STATUS INDICATION
The actual interface’s status is indicated by its bi-color indication LED.
If the interface is inactive, the LED does not light at all.
Active status is indicated by red light of the LED.
The green light indicates user definable functions defined by Indicator Mode preset parameter
(see chapter 4.2.4).
If an error occurs during the interface operation, the indication LED starts to blink red constantly
– see Appendix B.
4. PAR AM ETER S
The parameters are divided in two basic groups – system parameters and preset parameters –
see pic. 4.
All parameters are stored in memory banks in internal memory of the interface. There is one
memory bank for system parameters and 24 memory banks for preset parameters. Whole content of
all memory banks can be changed by Bulk Dump SysEx Messages ([1] to [4] on pic. - see description
of System Exclusive communication).
After each interface reset the system memory bank is loaded in system edit buffer. Some system
parameters can be changed during the device operation by MIDI System Exclusive communication
[12]. These settings are temporary only! To keep the changed parameters for future use (after next
restart of the instrument) they must be saved in system memory bank [8] by SysEx command (see
description of System Exclusive communication).

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
6
Pic. 4 – Structure of internal interface’s memory
The default preset memory bank (see chapter 4.1.2) is loaded into preset edit buffer [5] after
each restart/reset of the interface. Actual preset can be changed by standard MIDI Program Change
command (see chapter 5.1.5) or SysEx command (see description of System Exclusive
communication). When the preset is changed, the content of selected preset memory bank is loaded
into preset edit buffer [5].
The preset parameters can be changed during operation in preset edit buffer by MIDI Control
Changes [11]. All changed settings can be saved in any of the preset memory banks [7] by MIDI
Control Changes (see chapter 5.1.2.3) or SysEx command (see description of System Exclusive
communication).
4.1. SYSTEM PARAMETERS
The system parameters control the basic function of the interface. System parameters are
independent on the actual preset settings.
For the factory settings or “Factory reset” SysEx file see table 1 bellow.
Table 1 – Range of valid values and default values of system parameters
Valid values Default values (Factory Reset)
Parameter name [dec] [hex] [dec] [hex] Note
MIDI Channel 0 ~ 15 00 ~ 0F 0 00 Chnl Nr. 1
Default Preset 0 ~ 23 00 ~ 17 0 00 Preset Nr. 1
Autoreset 0 ~ 1 00 ~ 01 1 01 Enabled
System parameters in system edit buffer (expect of default preset program) can be set by MIDI
SysEx commands ([12] on pic. 4). These settings are valid immediately after the command is received.
However all changes / settings of the system parameters executed in edit buffer are temporary only.
For further use (after the instrument restart), these parameters should be saved in system memory
bank by MIDI SysEx command (see description of System Exclusive communication).
System parameters in system memory bank can be backed-up ([4] on pic. 4) and restored by
Bulk Dump SysEx Messages ([2] on pic. 4, see description of System Exclusive communication).
To activate the restored / new values of the system parameters, it is necessary to reset the
interface after restoring the system memory from Bulk Dump.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
7
4.1.1. MIDI CHANNEL
The parameter selects the MIDI channel number for the communication. It is possible to choose
any of the 1-16 channels. Valid values of the parameter are 0 to 15. Value 0 is for MIDI channel Nr.1,
value 1 selects channel Nr. 2 etc. up to value 15 which selects MIDI channel Nr. 16.
The factory setting is MIDI channel Nr.1 (see table 1). If necessary, MIDI channel number can be
user changed.(see description of System Exclusive communication).
4.1.2. DEFAULT PRESET
The parameter specifies the default user preset (memory bank) to be loaded after the interface is
turned on (interface reset). Value 0 is for preset Nr.1, value 1 selects Nr. 2 etc. up to value 23 which
selects preset Nr. 24.
Preset Nr. 1 is set as default during factory reset (also see table 1). Default preset number can
be changed by user (see description of System Exclusive communication).
4.1.3. AUTORESET
The parameter disables (parameter value 0) or enables (parameter value 1) automatic hardware
reset procedure if an MIDI communication error occurs (error Nr. 5 – see appendix B).
If the Autoreset is disabled the interface stops working after MIDI communication error. The error
status is indicated by indication LED (
see Appendix B). To resume the operation, the interface must be
switched off and then on manually.
If the Autoreset is enabled and an error occurs in MIDI communication, only short gap in the
communication appears and the device continues to work. No user action is necessary in such case.
The Autoreset function is enabled during factory reset (also see table 1). If necessary, the
Autoreset can be switched off by user (see description of System Exclusive communication).
4.2. PRESET PARAMETERS
The preset parameters set how MIDI notes, Control Changes and other commands are going to
control keyboard and pitch shift circuits of the instrument.
Following table describes the factory settings. All 24 factory preset parameter banks include the
same values (see table 2 bellow ).
Table 2 – Range of valid values and a default values of preset parameters
Valid values Default values
(Factory Reset)
Adjustable by MIDI
CC Nr.
Parameter name
[dec] [hex] [dec] [hex] [dec] [hex]
Key Shift 0 ~ 79 00 ~ 4F 48 30 16 10
Chnl Aftertouch Amount 0 ~ 127 00 ~ 7F 0 00 17 11
Pitch Bend Range 0 ~ 127 00 ~ 7F 127 7F 18 12
Indicator Mode 0 ~ 2 00 ~ 02 1 01 19 13
Actual values of the preset parameters in edit buffer can be edited by MIDI controllers (Control
Changes) Nr. 16 to 19 during the instrument operation ([11] on pic. 4).
All edited values of the parameters are stored in the preset edit buffer only. The content of the
buffer is saved temporarily only (see pic. 4), till the next preset change or the instrument switch off or

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
8
the interface reset. To keep the edited values of the parameters for permanent use, it is necessary to
save them from the preset edit buffer into a preset memory bank ([7] on pic. 4).
There are 24 available spaces for user settings. Saving the values in a preset memory bank is
done by MIDI Control Changes Nr. 118 (see chapter 5.1.2.3) or by the MIDI System Exclusive
command (see manual for SysEx communication).
Preset parameters in a preset memory bank can be backed-up ([3] on pic. 4) and restored by
Bulk Dump SysEx Messages ([1] on pic. 4, see description of System Exclusive communication). To
activate the restored / new preset, it is necessary to change / switch the desired preset number
by the MIDI program change.
4.2.1. KEY SHIFT
The interface accepts 49 MIDI notes (four octaves) only (same range as the original VP-330 /
RS-550 keyboard). The range of acceptable MIDI notes can be shifted by “Key Shift” parameter in
whole scale of MIDI notes. One step is equal to one semitone. Valid range of shift is from 0 to +79
semitones (value of the parameter can be from 0 to 79).
If no shift is chosen (i.e. parameter value is equal to 0), lowest acceptable MIDI key corresponds
to MIDI note Nr. 0 and highest key corresponds to MIDI note Nr. 48. If shift is +1 semitone (parameter
value is equal to 1), lowest key corresponds to MIDI note Nr. 1 and highest key corresponds to MIDI
note Nr. 49. Etc. up to maximum shift of+79 semitones (for detail see pic. 5.)
The parameter value in preset edit buffer can be set anytime during operation by MIDI Control
Change Nr. 16 – see chapter 5.1.2.2.
4.2.2. CHNL AFTERTOUCH AMOUNT
Frequency of the main oscillator of the instrument can be detuned down with Channel Aftertouch
MIDI command - instrument’s function PITCH SHIFT is controlled by MIDI Channel Aftertouch.
The parameter sets the depth of Channel Aftertouch modulation of the instrument’s oscillator.
Basic (default) detuning is set by the regulators on the left panel of the instrument. This basic value
can be increased to maximal possible detuning by Channel Aftertouch MIDI command (see pic. 6).
Value of the Channel Aftertouch Amount parameter can be set from 0 to 127. If the value is
equal to 0, Channel Aftertouch MIDI command doesn’t affect basic (default) instrument’s oscillator
frequency at all. If parameter value is set from 1 to 127, the oscillator frequency is decreased directly
proportionally to the Channel Aftertouch command value.
The parameter value in edit buffer can be adjusted anytime during operation by MIDI Control
Change Nr. 17 – see chapter 5.1.2.2.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
9
Pic. 5 – Effect of “Key Shift“ parameter

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
10
Pic. 6 – Pitch Shift function
a) Basic detuning is set by PITCH SET knob and
PITCH SHIFT slider on the instrument’s panel. Further
decrease of the frequency via MIDI commands (CHANNEL
AFTERTOUCH and PITCH BEND) is possible in the range
of the knob position and maximal possible detuning – see
arrows on the picture.
b) If the PITCH SET knob is set to H (max clockwise)
and PITCH SHIFT slider to NORMAL (max to the right),
the range of decreasing of the oscillator frequency via MIDI
commands (CHANNEL AFTERTOUCH and PITCH BEND)
is in maximal possible range – see arrows on picture.
c) If PITCH SET knob is set to L (max
counterclockwise) and PITCH SHIFT slider to DOWN (max
to the left), the basic detuning is set to the instrument´s
maximum, so there is no space for further decreasing of
the oscillator frequency. It means, that CHANNEL
AFTERTOUCH and PITCH BEND MIDI commands have
no affect on the main oscillator frequency.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
11
4.2.3. PITCH BEND RANGE
Frequency of the main oscillator of the instrument can be detuned down with Pitch Bend MIDI
command (pitch bend wheel, joystick, etc.) - PITCH SHIFT is then controlled by MIDI command Pitch
Bend. The “Pitch Bend range” parameter sets the depth of the Pitch Bend MIDI command modulation
of the instrument’s oscillator. Basic (default) detuning is set by the regulators on panel of the
instrument. It can be further increased to its maximal possible detuning range by Pitch Bend MIDI
command (see pic. 6).
Value of the parameter can be from 0 to 127. If value is equal to 0, Pitch Bend MIDI command
doesn’t affect basic (default) instrument’s oscillator frequency. If the parameter value is set in the range
of 1 to 127, the oscillator frequency is decreased proportionally to the value of Pitch Bend command.
The 127 value corresponds to a maximal possible range - Pitch Bend command value -8192.
Note that only bending down is possible (only values from –8192 to 0 of Pitch Bend command
are accepted – see chapter 6).
The parameter value in preset edit buffer can be set anytime during the operation by MIDI
Control Change Nr. 18 – see chapter 5.1.2.2.
4.2.4. INDICATOR MODE
The parameter sets the function of bi-color indication LED. Value of the parameter can be from 0
to 2. These values set three possible modes: ”Off “ (parameter value 0), ”Keys On“ (parameter value
1) and ”MIDI Event“ (parameter value 2).
The LED indicator works only if the interface is active (i.e. the instrument is switched to MIDI
mode – see chapter 3.2). If the interface is inactive, LED indicator doesn’t light.
Mode ”Off°“
Indicator is always switched off. The indication LED lights red only and it indicates that the
interface is turned on and active.
Mode ”Keys On“
In this mode, LED indicator is copying status of a keys pressed by MIDI Note-On command. The
indication LED lights green if at least one key pressed via MIDI Note-On command is active.
Mode ”MIDI Event “
In this mode, the indication LED indicates any incoming MIDI commands acceptable by the
interface. MIDI data going through the interface (MIDI ”Thru“ function) are not indicated. When
acceptable MIDI data is received, the LED blinks green. If the data flow is continuous (data more
frequent than approx. 120 ms), the green LED lights constantly.
The parameter value in preset edit buffer can be set anytime during operation by MIDI Control
Change Nr. 19 – see chapter 5.1.2.2.
5. MIDI IMPLEM ENTATION
VP330-KBD / RS505-KBD interface can communicate by all available MIDI methods – it
recognizes MIDI channel commands, common system commands as well as SysEx MIDI commands.
5.1. CHANNEL COMMANDS
The interface recognizes channel MIDI commands "Note-Off", "Note-On", "Control Changes",
"Channel Aftertouch", “Pitch Bend“ and "Program Change". So-called Running Status mode of MIDI
communication is fully provided. The commands are received on the channel defined by the MIDI
Channel system parameter (see chapter 4.1.1).

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
12
5.1.1. NOTE ON/OFF
The interface accepts Note-On and Note-Off commands in the range of max. 49 notes. Accepted
note numbers are defined by Key Shift preset parameter (see chapter 4.2.1).
Since the VP-330 / RS-505 are fully polyphonic instruments, the interface can work fully
polyphonically too.
5.1.2. CONTROL CHANGES
The interface uses standard MIDI controllers (Control Changes) Nr. 64, 120, 121 and 123. Some
other controllers are used for temporary setting of parameters values in edit buffer (CC Nr. from 16 to
19) and for control of interface’s functions (CC Nr. 118 and 119).
5.1.2.1. STANDARD CONTROLLERS
CC 64 – Hold
The controller works standard way: holds tone generator of the instrument playing (active) during
the time when the Hold command is active (hold pedal pressed). Values from 64 to 127 are recognized
as on-status, values from 0 to 63 as off-status.
Note: This controller works only with tones played by MIDI notes. It doesn’t hold notes
pressed on instrument’s own keyboard!
CC 120 – All Sound Off
All tone generator of the instrument are switched off immediately after receiving of this controller
– independently on MIDI commands Note-On received previously.
Note: This controller works only with tones played by MIDI notes. It doesn’t hold notes
pressed on instrument’s own keyboard!
CC 121 – Reset All Controllers
Immediately after receiving of this controller, CC64 and Pitch Bend are set to their initial status:
CC64 Hold Æ off ( value 0)
Pitch Bend (Wheel) Æ middle position (value 0)
All MIDI notes hold with CC64 are released and Pitch Bend effect to instrument’s PITCH SHIFT
function is released.
CC 123 – All Notes Off
Same as with All Sound Off, all tone generator of the instrument are switched off immediately
after receiving of this controller – independently on MIDI commands Note-On received previously.
Note: This controller works only with tones played by MIDI notes. It doesn’t hold notes
pressed on instrument’s own keyboard!
5.1.2.2. CONTROLLERS FOR PRESET PARAMETERS SETTING
These Control Changes set values of parameters in preset edit buffer. All changes takes effect
immediately after the commands are received. But all these changes are temporary only (see [11] on
pic. 4) - until the preset is changed or the instrument is switched off or the interface reset.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
13
CC 16 – Controller : Key Shift
Received value of the controller Nr. 16 is converted to the value of the Key Shift parameter (see
chapter 4.2.1).
Values of the controller from 0 to 79 correspond to the parameter value directly.
Values of the controller from 80 to 127 are converted to closest possible value (i.e. 79).
CC 17 – Controller : Chnl Aftertouch Amount
Received value of the controller Nr. 17 is converted to the value of the Aftertouch Amount
parameter (see chapter 4.2.2).
Values of the controller from 0 to 127 correspond to the parameter values (0 to 127) directly.
CC 18 – Controller : Pitch Bend Range
Received value of the controller Nr. 18 is converted to the value of the Pitch Bend Range
parameter (see chapter 4.2.3).
Values of the controller from 0 to 127 correspond to the parameter values (0 to 127) directly.
CC 19 – Controller : Indicator Mode
Received value of the controller Nr. 19 is converted to the value of the Indicator Mode parameter
(see chapter 4.2.4).
Values of the controller from 0 to 2 correspond to the parameter value directly.
Values of the controller from 3 to 127 are converted to closest possible value (i.e. 2).
5.1.2.3. CONTROLLERS FOR INTERFACE’S FUNCTIONS CONTROL
CC 118 – controller : Save Edit Buffer
The controller Nr. 118 saves the content of preset edit buffer to the permanent memory banks of
the interface (see [7] on pic. 4).
Valid values of the controller are from 0 to 23 (it corresponds to memory banks 1-24). If another
value of the controller is received, the whole command is invalid and it is ignored by the interface
If values from 0 to 23 are received, data from preset edit buffer will be stored into preset memory
bank which is specified by the controller value - 0 for bank Nr. 1, 1 for bank Nr. 2 etc. up to 23 for bank
Nr. 24.
CC 119 – controller : Reset
The controller Nr. 119 resets the interface. Value of the controller must be always 0 – the
command is unacceptable and it is ignored for all other values.
The interface is deactivated immediately after this controller is received. All circuits of the
interface are set to default status (same as after the instrument is switched on – see chapter 3.1). This
controller is equivalent to common system command Reset (see chapter 5.2).
5.1.3. CHANNEL AFTERTOUCH
Channel Aftertouch MIDI command can affect instrument’s PITCH SHIFT function – detuning the
main oscillator of the instrument down. The maximal detune depth depends on Chnl Aftertouch
Amount preset parameter settings (see chapter 4.2.2).
The interface accepts whole range of the command values – from 0 to 127.
For value 0, the oscillator detune is set by panel regulators of the instrument only. For values
from 1 to 127, the oscillator detuning is increased directly proportionally to the value of the command.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
14
5.1.4. PITCH BEND
Pitch Bend (Wheel) MIDI command can control instrument’s PITCH SHIFT function – detuning
of main oscillator of the instrument. The maximal depth of detuning is set by preset parameter “Pitch
Bend Range” (see chapter 4.2.3).
Since the instrument can detune the main oscillator down only, the interface accepts the
command values from -8192 to 0 only (i.e. only down from the center position of the pitch wheel,
joystick, etc.). Values from +1 to +8191 of the MIDI command are ignored.
For value 0, the oscillator detune is set by panel regulators of the instrument only. For values
from –1 to –8192, the oscillator detune is increased proportionally to the value.
5.1.5. PROGRAM CHANGE
Program Change MIDI command selects active user preset of the interface. Only program
numbers from 0 to 23 are accepted and they correspond to presets numbers 1 to 24. Program
numbers 24 to 127 are ignored.
When acceptable Program Change command is received, all tones activated via MIDI notes are
muted. When the next MIDI Note-On command is received, the interface starts to work normally
accordingly to the parameters of newly selected preset.
5.2. COMMON SYSTEM COMMAND - RESET
The interface recognizes System Rest command only. When the Reset command is received,
complete hardware reset of the interface is executed – all interface’s circuits are set to their default
values (the same as after the instrument is switched on – see chapter 3.1).
5.3. SYSTEM EXCLUSIVE MESSAGES
The interface uses System Exclusive communication protocol for bi-directional memory bulk
dumps and some system functions. Detailed description of the System Exclusive communication is in
separate manual.
Attached CD-ROM contains software generator for creation of SysEx Messages (see pic. 7)
necessary for communication between the interface and MIDI host system The generator is also
available on manufacturer’s web-pages.
The generator creates any kind of message for control of the interface easily and without
knowledge of difficult hexadecimal calculations. The generator is Java script based, so it is computer
platform independent. Any internet browser can be used.
For easy calculation of the checksum contained in System Exclusive messages, Checksum
Calculator software can be used (see pic. 8). The calculator is available on attached CD-ROM or on
manufacturer’s web-pages.
The generator is Java script based, so it is computer platform independent. Any internet browser
can be used.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
15
Pic. 7 – SysEx Messages Generator window
Pic. 8 – Checksum Calculator window

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
16
6. POSSIBLE LIMITATION DURING THE INTERFACE USAGE AND RECOMMENDED SETTINGS
As mentioned earlier in chapter 5.1.4, MIDI Pitch Bend command can modulate the pitch shift of
instrument’s main oscillator only in one direction – the oscillator can be detuned down only. Moving
the pitch bend lever / wheel on a master MIDI device up from the center position will not take any effect
on the VP-330 / RS-505 instrument. The range of the oscillator detuning via MIDI commands is
affected not only by values of these commands but also by settings of controllers on the instrument’s
panel. For details see picture 6. To get the maximal range of the oscillator detuning via MIDI
commands, use recommended setting shown on pic 6b.
For VP-330 instrument: If too many keys is pressed simultaneously via MIDI notes and on the
instrument's own keyboard (approx. over 20 keys simultaneously both MIDI and keyboard), a small
amount of distortion in the instrument's sound can be heard.
This distortion doesn't occur if the instrument is controlled via MIDI notes only or only by its own
keyboard only. If the instrument is controlled solely from MIDI or own keyboard, any number of keys
(up to full range 49 keys) can be pressed simultaneously without any changes of the instrument's
sound.
For RS-505 instrument: The Second Touch function is not available if the keyboard is controlled
via MIDI. If any (at least one) key is pressed by a MIDI Note command, the function is disabled and it is
not working. When all MIDI notes are “Off” and own instrument’s keyboard is use, the Second Touch
function works normally.
7. TECHNICAL SPECIFICATION
MIDI bus : fully according to MIDI Manufacturer Association standards
MIDI connectors : 2x DIN 41524 (5 pins / 180°)
Transit data delay MIDI IN Æ THRU : max. 1 ms, typ. 0,32 ms
Electrical design : under the regulations of the ČSN EN 60335-1+A55,
ČSN EN 60335-2-45
EMC : under the regulations of the ČSN EN 55014
Operating environment : standard
Range of operating temperature : +10 to +35 °C
Relative environmental humidity : up to 85 %
8. WARRANTY CONDITIONS
The equipment is provided with thirty-month warranty starting from the date of the equipment
take-over by the customer. This date must be specified on warranty list together with dealer's
confirmation.
During this period of time, all defects of equipment or its accessories, caused by defective
material or faulty manufacturing, will be removed free of charge.
Warranty repair is asserted by the customer against the dealer.
Warranty period is to be extended for the time period, during which the product was under the
warranty repair.
The relevant legal regulations take effect in case of cancellation of purchase contract.
The customer will lose the right for free warranty repair, if he will not be able to submit properly
filled out warranty list or if the defects of the product had been caused by:
- unavoidable event (natural disaster),
- connecting the device to the incorrect supply voltage,
- inputs or outputs overloading by connecting the signals source or load source with not-
corresponding characteristics etc.,

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
17
- faulty equipment operation, which is at variance with the instructions referred-to in the operating
manual,
- mechanical damage caused by consumer during transportation or usage of equipment,
- unprofessional interference with the equipment or by equipment modification without
manufacturer’s approval.
APPENDIX A. - MIDI IMPLEMENTATION CHART
MIDI IMPLEMENTATION CHART
Device : VP330-KBD / RS505-KBD Date : 10 / 2015
Model : 8-440 / 8-441 Version : 1.0
Function Transmission Reception Remarks
Basic
Channel
Default
Changed
X
X
1~16
1~16
1
)
1
)
Mode Default
Messages
X
X
Mode 3
X Not Altered
Note Number X 0~127
2
)
Velocity Note ON
Note OFF
X
X
O
X
After
Touch
Key's
Channel's
X
X
X
O
Pitch Bender X O
Control
Changes
16 to 19
64
118, 119
120
121
X
X
X
X
X
O
O
O
O
O
Device specific – see description
Hold
Device specific – see description
All Sound Off
Reset All Controllers
Program Change X O Preset Change (0~23)
System Exclusive O O See description
System
Common
Song Position
Song Select
Tune
X
X
X
X
X
X
System
Real Time
Clock
Command
X
X
X
X
Others Local ON/OFF
All Notes Off
Active Sensing
Reset
X
X
X
X
X
O
X
O
Notes :
1
) Can be changed by user
2
) Position of 49 acceptable notes depends on Key Shift parameter setting
Mode 1 : OMNI ON, POLY
Mode 3 : OMNI OFF, POLY
Mode 2 : OMNI ON, MONO
Mode 4 : OMNI OFF, MONO
O : Yes
X : No

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
18
APPENDIX B. - ERROR STATUS INDICATION
In some extreme cases, an error can occur during the device operation where correct processing
of MIDI data is not allowed. In such case, the VP330-KBD / RS505-KBD interface stops its operation
and user is informed about the error status by blinking of the red indication LED. Number of blinks
specifies the error type (number) – see table 3.
Table 3 – Error status indication
Error description Number
of blinks Name Indicated problem
Automatic
reset
1 EEPROM
Malfunction
MIDI interface internal memory does not communicate with CPU -
reset the interface by switching the instrument off and on. If the error
remains after the reset it is a hardware failure. Please contact the
authorized service.
Rejected
2 EEPROM
Busy
MIDI interface internal memory is reacting too slowly to the CPU
requirements - reset the interface by switching the instrument off
and on. If the error remains after the reset it is a hardware failure.
Please contact the authorized service.
Rejected
3 EEPROM
Failed Cell
Invalid data in the internal memory MIDI cell - reset the interface by
switching the instrument off and on and then execute “Factory
Reset”. If the error remains after the reset it is a hardware failure.
Please contact the authorized service.
Rejected
4 DAC
Malfunction
Internal D/A converter of the MIDI interface does not communicate
with CPU - reset the interface by switching the instrument off and
on. If the error remains after the reset it is a hardware failure. Please
contact the authorized service.
Rejected
5 MIDI Buffer
Overflow
MIDI data loss at the MIDI input - too much MIDI data has been sent
to the instrument. Enabled
There are two types of errors – working and fatal errors.
Fatal errors (Nr. 1 to 4) disable correct operation of the interface’s CPU. If that error occurs,
processing of all data and reading of all control commands is stopped and the interface has to reset for
normal working mode by turning the whole instrument off and then on after a moment.
Working error (Nr. 5) occurs if a MIDI caching buffer overflows. This error doesn’t block CPU
operation, it only does not allow correct processing of incoming MIDI data. Further steps depend on
“Auto Reset“ system parameter setting (see chapter 4.1.3): If the Autoreset function is on, the interface
resets itself automatically and the instrument returns to normal working mode. If the Autoreset function
is off, it is necessary to turn the whole instrument off and then on again after a moment as in previous
case.
APPENDIX C. – FACTORY RESET
If necessary, complete factory reset of the interface can be executed. During this process, the
interface is initialized to the factory status (all parameters are set to the default values). The factory
reset process is launched by System Exclusive MIDI command:
F0 00 20 21 7F 5D 30 03 7F 71 F7 [hex]
After successful factory reset completion, the indication LED blinks six times in red.
WARNING - All data stored by user in the internal interface’s memory are fully erased
after the factory reset. It is recommended to back up all user data by the "BULK DUMP DATA
REQUEST" and "BULK DUMP DATA SAVE / LOAD" messages before the factory reset procedure.

VP330-KBD / RS550-KBD VP-330 / RS-550 MIDI Interfaces
Model 8-440 / 8-441 ver. 1.0
Copyright © 2015 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
19
APPENDIX D. – LOOP IN MIDI COMMUNICATION
When VP330-KBD / RS505-KBD interface is controlled by a sequencer (HW or SW) and the
devices are interconnected bi-directionally (with both MIDI cables) and the sequencer isn’t set
correctly, communication loop might occur and the entire MIDI system “freezes”. In this case all MIDI
data incoming from sequencer to interface’s input are transmitted to interface’s output (THRU function)
and back to the sequencer thus. This causes infinite cyclic transfer of the same MIDI data.
To avoid this situation, MIDI thru function must be turned off in a sequencer. This sequencer
function is usually called MIDI ECHO or MIDI THRU. For more details check the documentation of your
sequencer.
APPENDIX E. – AUTOMATIC ACTIVATION OF INTERFACE
If manual switch of the interface is not installed and it is replaced by jumper (see installation
manual for more info), the interface becomes active immediately after initialization sequence (i.e. after
the instrument is switched on – see chapter 3.1). MIDI communication is allowed but the interface
doesn’t affect the instrument until the first MIDI event arrives at MIDI input – the instrument can be
used the same way as without installed interface.
After first MIDI command is receipted, the interface turns into operation and control over
instrument’s keyboard and PITCH SHIFT circuits. The instrument’s keyboard and all controllers on
instrument’s panel are still fully functional.
To return to “non-MIDI” status where the instrument isn’t affected by the interface, the interface
has to be reset. It is necessary to either turn the instrument off and then turn it on after a moment or
reset the interface run by software command – common system MIDI command “Reset”, by SysEx
command “HW Reset” (see description of SysEx communication) or by MIDI controller (CC) Nr. 119
(see chapter 5.1.2.3).

7