CHD Elektroservis   Korg 770 / 700S / 900PS MIDI Interface (Model 8-430, v. 1.0) - Help


System Parameters    Preset Parameters    System Functions    SysEx Message
 

System Parameters ^^^^^

These parameters affect basic functions of the interface. They are valid for each of presets. Note that their changes become evident till after next reset of the interface!

MIDI Channel
Number of the MIDI channel used for the communication with a host MIDI system can be selected with this parameter.

Auto Local
The parameter allows automatic turning of the interface to "Keyboard" mode after first valid Note-On MIDI command is received.

Auto Reset
The parameter allows automatic reset of the interface when a MIDI communication problem occurs.

Gate Interrupt Duration
The parameter defines duration of interrupt pulses for instrument's envelope retriggering generated by the interface for non-legato playing style while the arpeggio is on. The duration is defined by the following formula:
Pulse duration = ({parametr value} + 5) / 5 [ms]

Bulk Dump Data Load - Generate button
Generated Bulk Dump message changes the values of all parameters in the system memory bank. Requested values of all system parameters must be set before the Bulk Dump Message is generated.

Bulk Dump Data Request - Generate button
Generated Bulk Dump message is inquiry for the content of the system memory bank. Immediately after the message receiving the interface sends the Bulk Dump System Data Save / Load message as reply.
 

Preset Parameters ^^^^^

These parameters define how the MIDI commands are controlling VCO / GATE circuits of the Korg instrument. 128 user presets are available in preset memory bank for saving of these parameters.

Preset Number
Selection of the number of preset in preset memory bank to which the data will be stored (Bulk Dump Data Load) or from which the data will be read (Bulk Dump Data Request). This number must be chosen always!

Key Shift
The interface accepts 48 MIDI notes i.e. four octaves keyboard range. The acceptable range can be shifted / transposed by Key Shift parameter in whole range of MIDI notes. Each value corresponds to one semitone.

Pitch Bend Range
The parameter sets the maximum range of detuning by the Pitch Bend (Pitch Wheel) MIDI command. Value of the parameter is from 0 to 12. If the value is set to 0, the detuning is disabled and the Pitch Bend command is ignored. Values 1 - 12 sets the maximum detune range in semitones, i.e. +-1 octave for the value equal to 12.

Aftertouch Bend Range
Frequency of the VCO can be detuned ("bent") by Channel Afterouch MIDI command. The parameter sets the amount of Channel Afterouch command modulation of the VCO frequency. Maximal VCO frequency shift is +-4 semitones.
If the parameter value is equal to 64, Channel Aftertouch MIDI command doesn't affect instrument's VCO frequency. For parameter values from 65 to 127, VCO frequency is increased (bent up). For parameter values from 63 to 0, VCO frequency is decreased (bent down).

Note Buffer Size
The parameter sets the number of last received MIDI Notes that are kept in internal interface's note buffer.

Arpeggio Mode
There are five arpeggiator modes available:
"Off" - the arpeggiator is off
"Up" - tones from first received Note (pressed key) to last received Note.
"Down" - tones from last received Note (pressed key) to first received Note
"Up-Down 1" - tones from first received Note (pressed key) to last received Note and then in opposite direction
"Up-Down 2" - tones from first received Note (pressed key) to last received Note and then in opposite direction (Similar to "Up-Down 1", but first and last received Notes of the chord are not repeated).
The arpeggiated chord can content up to eight tones. Note that the arpeggio chord tones are played in the order they were received (from first to last or vice versa) and not in their pitch order (from low to high or vice versa)!

Arpeggio Clock Source
The arpeggiator rate can be synchronized from various tempo sources:
"Fixed" - internal clock generator. The fixed tempo is set by Arpeggio Rate parameter.
"MIDI Clock" - external MIDI clock. MIDI Clock dividing ratio (relative arpeggio speed) is set/adjusted by Arpeggio Rate parameter.
"CC" - a special mode where the arpeggiator is controlled directly by CC #22. Each time the CC #22 is received (any value), one clock pulse is generated and shifts the playing tone to the next tone in the chord.

Arpeggio Rate
The parameter selects the rate of synchronization clock pulses for arpeggiator if "Fixed" or "MIDI" modes are active (see Arpeggio Clock Source parameter). The parameter is ignored in "CC" mode.

Indicator Mode
The parameter sets the function of interface's green LED indicator. Four functions are available:
"Off" - The green LED indicator is turned off
"Gate" - The green LED indicator is copying the status of envelope generator - GATE signal.
"MIDI Event" - The green LED indicates acceptable incoming MIDI commands.
"Arpg Clock" - The green LED indicates clock pulses for arpeggiator for all three Arpeggio Clock sources.

Bulk Dump Data Load - Generate button
Generated Bulk Dump message changes the values of all parameters of a preset in permanent preset memory bank. The number of the requested preset must be set in the "Preset Number" box and requested values of all preset parameters must be set before the Bulk Dump Message is generated.

Bulk Dump Data Request - Generate button
Generated Bulk Dump message is inquiry for the content of a preset in permanent memory bank. The number of requested preset must be set in the "Preset Number" box before the Bulk Dump Message is generated. Immediately after the message receiving the interface sends the Bulk Dump Data Save / Load message as reply.
 

System Functions ^^^^^
These functions are launching a special procedures:

Preset Request
It is request for actual (just active) preset number. As a response, the interface transmits the message:
   F0 00 20 21 ii 54 50 00 dd xx F7 [hex]
where "dd" databyte (0 to 127) is the number of actual preset (1 to 128).

Preset Change
The actual (just active) preset can be changed - an equivalent for the standard Channel MIDI command "Program Change".

Save Edit Buffer to Preset Memory
The actual values of preset parameters will be stored from the edit buffer to selected preset number in preset memory bank.

Interface Reset
The message for the hardware warm reset launching or for the total factory reset procedure will be generated.

SW Version Request
The request for the installed firmware version will be generated. As a response, the interface transmits the message:
   F0 00 20 21 ii 54 50 04 dd xx F7 [hex]
where nibbles of the "dd" databyte define the number of firmware version.

SysEx Message ^^^^^
The text form of generated SysEx Message can be set with a help of two select-boxes:

Select Hex Byte Form
The text form of generated hexadecimal bytes can be chosen by this select-box. Requested form must be selected before any "Generate" button is pressed.

Select Delimiter
The delimiter between the generated hexadecimal bytes can be chosen by this select-box. Requested delimiter must be selected before any "Generate" button is pressed.

Text Area
The System Exclusive Messages are generated in a hexadecimal form as the text in this area.

Reset Button
This button sets all parameters to their default values and it clears the text-area too.