Eos, Congo and Cobalt Family Consoles Smartfade, Software Version 3.0.0 Express, Software Version 3.1 ColorSource Console, EchoTouch Response Mk2 DMX/RDM Gateways Software Version 1.1.1+ 4 Port Net3 Gateway and Response DMX/RDM Gateway Software Version 5.1.0+, ACN Mode 4 Port Net3 Gateway, Software Version 4.0.5.9.0.36, Net2 Mode Observations 2 Port Net3 Gateway, Software Version 4.0.5.9.0.36, Net2 Mode Observations 2 Port Net3 Gateway, Software Version 1.0.0.9.0.83, ACN Mode 2 Port ETCNet2 Node, Software Version 4.1.3.9.0.6 Four Port ETCNet2 Node, Software Version 4.1
If you need further information, the book " Recommended Practice for DMX512: A guide for users and installers " is highly recommended and available from The Esta Foundation .
There are several areas where DMX timing can vary in a DMX packet. Each packet follows the format shown above.
First, a break occurs telling the receiver that this is the start of a new packet. Then the line is driven high for the Mark after Break (MAB) time. Then follows the start code, followed by the "post start" time. Then there follows the channel data, during which the line can be high (idle) for a variable amount of time between channels, known as the interbyte time. Finally after the last channel the line goes high (idle) for the interpacket delay time until the break of the next packet (also known as the Mark before Break (MBB) time).
The following are the minimum values allowable by the ESTA DMX-512A standard :
Timing Parameter
Minimum
Maximum
Break
92μs
Note 1
Mark-After-Break
12μs
Note 1
Post-Start
8μs (Two stop bits)
Note 1
Interbyte
8μs (Two stop bits)
Note 1
Interpacket
8μs (Two stop bits)
Note 1
Note: These timings can be any value to add up to make a packet length of up to one second.
As you can see a very wide variety of timings is permissible. For reference, here are the timings for some different ETC products.
Eos, Congo and Cobalt Family Consoles
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
36
142
128
24
12
12
Fast
36
142
128
27
18
16
Medium
36
142
128
34
30
30
Slow
36
142
128
42
46
44
Smartfade, Software Version 3.0.0
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
0
176
16
22
0
0
Fast
12
176
44
27
4
2000
Medium
16
220
100
34
16
4000
Slow
36
264
100
50
36
8000
Express, Software Version 3.1
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
32
94
26
26
12
1160
Fast
32
138
28
26
12
1160
Medium
32
184
32
26
12
2120
Slow
32
270
50
31
12
6960
ColorSource Console, EchoTouch
Break
Mark After Break (min)
Break to Break
Update Rate (pkts/sec)
Maximum
200
44
25048
39
Fast
240
44
27475
37
Medium
280
84
33700
30
Slow
320
84
42482
24
Response Mk2 DMX/RDM Gateways
Software Version 1.1.1+
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
0
176
12
22.9
0
200
Fast
4
176
44
26.8
4
2000
Medium
4
220
60
28.9
4
4000
Slow
36
264
60
49.3
36
8000
4 Port Net3 Gateway and Response DMX/RDM Gateway
Software Version 5.1.0+, ACN Mode
PORTS 1&2
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
8
176
12
22.8
8
180 - 432
Fast
12
192
60
25.3
12
2320
Medium
12
240
60
25.3
12
4260
Slow
12
288
60
25
12
8320
PORTS 3&4
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
8
194
12
23.9
8
150-400
Fast
12
188
48
25.2
12
2260
Medium
12
240
64
25.3
12
4140
Slow
12
272
64
45
48
8560
4 Port Net3 Gateway, Software Version 4.0.5.9.0.36, Net2 Mode
Observations
Variable DMX output speed is not implemented
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Any
8
126-132
56
24
8
784-1260
2 Port Net3 Gateway, Software Version 4.0.5.9.0.36, Net2 Mode
Observations
Variable DMX output speed is not implemented
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Any
8
176
12
23
8
1260
2 Port Net3 Gateway, Software Version 1.0.0.9.0.83, ACN Mode
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
8
176
12
22
8
176
Fast
8
176
12
24
8
2160
Medium
12
240
60
29
12
4200
Slow
13
288
60
33
12
8240
2 Port ETCNet2 Node, Software Version 4.1.3.9.0.6
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
8
88-93
48
22
8
8
Fast
12
156
48
25
12
90
Medium
16
184
74
27
16
162
Slow
24
226
100
31
24
254
Four Port ETCNet2 Node, Software Version 4.1
Post Start (μs)
Break (μs)
MAB (μs)
Packet (ms)
Interbyte (μs)
Interpacket Idle (μs)
Maximum
8
94
8
23
8
1140
Fast
8
142
13
26
8
3040
Medium
8
188
18
27
8
5160
Slow
8
282
33-35
32
8
8800