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In systems with multiple controllers it is necessary to
communicate with the control modules using party mode (PY=1) of operation.
The MDrive Motion Control nodes in the system are configured in software
for this mode of operation by setting the Party Flag (PY) to True (1). It
is necessary for all of the nodes in a system to have this configuration
selected. When operating in party mode each MDrive Motion Control in the
system will need a unique address, or name, to identify it in the system.
This is accomplished by using the software command DN, or Device Name. For
example, to set the name of an MDrive to "A" you would use the
following command: DN=65 or DN="A" (65 is the ASCII decimal
equivalent of uppercase A). The factory default name is "!". The
asterisk character "*" is used to issue global commands to every
device in the system. NOTE: When using the asterisk "*" in Party
Mode, typed entries and commands will not be echoed.
SET UP INSTRUCTIONS
In setting up your system for party operation, the most
practical approach is to observe the following steps:
1. Connect first MDrive Motion Control to the Host PC
configured for Single Mode Operation.
2. Establish communications and download program if
required.
3. Using the command DN, name the MDrive Motion Control.
This can be any upper or lower case ASCII character or number 0-9. (DN="A"{enter})
4. Set the party flag PY=1{enter}.
5. Type CTRL+J to activate the Party Mode.
6. Type AS CTRL+J (Save device name and Party Mode).
7. Remove power.
8. Repeat steps 1 through 7 for each additional MDrive in
the system.
Figure: Party Mode with Host PC
Data Cable Termination Resistors
Data Cable lengths greater than 15 feet (4.5 meters) are susceptible to
signal reflection and/or noise. IMS recommends 120 W
termination resistors at both ends of the Data Cables. An example of
resistor placement is shown above. For systems with Data Cables 15
feet (4.5 meters) or less, the termination resistors are generally not
required.
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MDI Communication Format
The following communication formats used by MDrive Motion Control
(MDI) units, began with pre-release firmware version 901.034.
{}
The contents between the {} symbols are transmitted.
{0D} Hex equivalent for a CR
(Carriage Return).
{0A} Hex equivalent for a LF
(Line Feed).
{DN} Represents the Device Name
being sent.
{CS} Check Sum; {ACK} 06 Hex; {NAK} 15 Hex
EM = Echo Mode; PY = PartY
Mode; CK= ChecK sum
The word {command} represents the immediate
command sent to the MDI.
Command Execution Time (CET) is the time the MDI
takes to execute a command. This varies from command to command and
usually is in the 1-5 millisecond range.
Parameter setting
|
Transmission
to MDI
|
MDI initial response
|
MDI final response
|
Notes
|
|
EM=0
& PY=0 CK=0
|
{command}
{0D}
|
{command}
(echoed back one character at a time as the character is entered)
|
CET
{0D} {0A} >
|
The
last character sent is the prompt >
|
|
EM=1
& PY=0 CK=0
|
{command}
{0D}
|
|
CET
{0D} {0A}
|
The
last character sent is the LF
|
|
EM=2
& PY=0
CK=0
|
{command}
{0D}
|
|
|
No
response except to PR and L commands
|
|
EM=3
& PY=0
CK=0
|
{command}
{0D}
|
|
CET
command
{0D} {0A}
|
Queued
response. The last character sent is the LF.
|
|
Parameter
setting
|
Transmission
to MDI
|
MDI
initial response
|
MDI
final response
|
Notes
|
|
EM=0
& PY=1
CK=0
|
{DN}
{command} {0A}
|
{command}
(echoed back one character at a time as the character is entered)
|
CET
{0D} {0A} >
|
The
last character sent is the prompt >
|
|
EM=1
& PY=1
CK=0
|
{DN}
{command} {0A}
|
|
CET
{0D} {0A}
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The
last character sent is the LF
|
|
EM=2
& PY=1
CK=0
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{DN}
{command} {0A}
|
|
|
No
response except to PR and L commands
|
|
EM=3
& PY=1
CK=0
|
{DN}
{command} {0A}
|
|
CET
command
{0D} {0A}
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Queued
response. The last character sent is the LF.
|
|
Parameter
setting
|
Transmission
to MDI
|
MDI
initial response
|
MDI
final response
|
Notes
|
|
EM=0
& PY=0
CK=1
|
{command}
{CS} {0D}
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{command}
(echoed back one character at a time as the character is entered)
|
CET
{ACK} or {NAK} >
|
The
last character sent is the prompt >
|
|
EM=1
& PY=0
CK=1
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{command}
{CS} {0D}
|
|
CET
{ACK} or {NAK}
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The
last character sent is the ACK or NAK
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|
EM=2
& PY=0
CK=1
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{command}
{CS} {0D}
|
|
|
No
response except to PR and L commands
|
|
EM=3
& PY=0
CK=1
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{command}
{CS} {0D}
|
|
CET
command {CS}
{ACK} or {NAK}
|
Queued
response. The last character sent is the ACK or NAK.
|
|
Parameter
setting
|
Transmission
to MDI
|
MDI
initial response
|
MDI
final response
|
Notes
|
|
EM=0
& PY=1
CK=1
|
{DN}
{command} {CS} {0A}
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{command}
(echoed back one character at a time as the character is entered)
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CET
{ACK} or
{NAK} >
|
The
last character sent is the prompt >
|
|
EM=1
& PY=1
CK=1
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{DN}
{command} {CS} {0A}
|
|
CET
{ACK} or
{NAK}
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The
last character sent is the ACK or NAK
|
|
EM=2
& PY=1
CK=1
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{DN}
{command} {CS} {0A}
|
|
|
No
response except to PR and L commands
|
|
EM=3
& PY=1
CK=1
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{DN}
{command} {CS} {0A}
|
|
CET
command {CS} {ACK} or {NAK}
|
Queued
response. The last character sent is the ACK or NAK
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Using
CHECK SUM
For communication using Check Sum,
the following 2 commands demonstrate sending
and receiving.
Sending
Command
1. Check Sum set to ZERO before first character is sent.
2.
All characters (ASCII values) are added to Check Sum, including the Device
Name DN (if PY=1), to the end of the command, but not including
terminator.
3.
Check Sum is 2's complement OR'd with Hex 80 (prevents Check Sum from
being seen as Command Terminator).
4.
Terminator Sent.
Example
command:
MR (space) 1
77 82 32 49
Decimal value
4D
52 20 31
Hex
77+82+32+49=240 Add
decimal values together
1111
0000
240
Change 240 decimal to binary
0000
1111
1's complement
0001
0000
Add 1 [2's complement]
1000
0000
OR result with 128
1001 000
144
result check sum value
Once the result is reached, add the check sum value of 144
to your string by typing: MR 1 (Alt Key + 0144) (use the symbol of 144 in your
string by holding down the Alt key and typing 0144).
Receiving
Command
1.
Check Sum set to ZERO.
2.
All characters are added to Check Sum.
3.
When receiving a Command Terminator, the lower 7 bits of the Check Sum
should be = to ZERO.
a) If not ZERO, then command is ignored and NAK echoed.
b) If ZERO, then ACK is sent instead of CR/LF pair.
4.
Responses to PR commands will be Check Summed as above, but the receiving
device should NOT respond with ACK or NAK.
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Figure: Party Mode with MDrive as Master
MDI
Party Mode Sample Codes
-
Download
this segment of code into the first MDrive Motion Control. After
downloading the program to the unit, follow the Set
Up instructions from the beginning of article. Be sure to set your
first unit with the unique address of A (device name is case
sensitive). Refer to figure above.
RC=25
'Run current
HC=5
'Hold current
MS=256
'Microstep selection
A=250000 'Acceleration
D=250000 'Deceleration
PG 1
'Enter program mode
S1=0,0
'Setup I/O 1 as an input low true
LB SU
'Start program upon power up
LB AA
'Label program AA
MR 104400 'Move
relative 104400 counts
H
'Hold program execution to complete the move
LB DD
'Label program DD
BR DD,I1=0 'Branch
to DD if I1=0
PR "Bex 1"
'Print device name B to execute program at address 1
H 2000
'Hold program execution 2000 milliseconds
PR "Cex 1"
'Print device name C to execute program at address 1
H 2000
'Hold program execution 2000 milliseconds
BR AA
'Branch to label AA
E
PG
'Exit program, return to immediate mode
-
Download
this segment of code into your second MDrive Motion Control. After
downloading the program to the unit, follow the previous party mode
instructions. Be sure to set your second unit with the unique address
of B (device name is case sensitive).
RC=25
'Run current
HC=5
'Hold current
MS=256
'Microstep selection
A=250000 'Acceleration
D=250000 'Deceleration
PG 1
'Enter program mode
LB BB
'Label program BB
MR 208000 'Move
relative 208000 counts
H
'Hold program execution to complete the move
E
PG
'Exit program, return to immediate mode
-
Download
this segment of code into your second MDrive Motion Control. After
downloading the program to the unit, follow the previous party mode
instructions. Be sure to set your third unit with the unique address
of C (device name is case sensitive).
RC=25
'Run current
HC=5
'Hold current
MS=256
'Microstep selection
A=250000 'Acceleration
D=250000 'Deceleration
PG 1
'Enter program mode
LB CC
'Label program CC
MR 300000 'Move
relative 300000 counts
H
'Hold program execution to complete the move
E
PG
'Exit program, return to immediate mode
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Questions? Contact IMS applications support:
Western U.S. Region Ph: (760)
966-3162, E-mail: wtech@imshome.com
Eastern U.S. Region
Ph: (860) 295-6102, E-mail:
etech@imshome.com
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