Lil'DMXter2
tm The Volt Meter of Digital Lighting Control |
The operation of the Lil'DMXtertm is designed to be intuitive, and as user friendly as possible. Many users will never need to know the technical details. But since the Lil'DMXtertm is a piece of reasonably accurate test equipment here are the specifications in gory detail.
TRANSMITTED DMX512 PARAMETERS | ||||
FUNCTION | DEFAULT | MINIMUM | MAXIMUM | RESOLUTION |
BAUD RATE | 250,000 | as per DMX512 | ||
BREAK LENGTH | 88S | 50S | 49144S (1) | 1S |
MARK AFTER BREAK | 8S | 3S | 49064S (2) | 1S |
INTERFRAME MARK TIME | 4S | 4S | 330S | 22S |
INTERPACKET MARK TIME | 4S | 4S | 1.442SEC | 22S |
DIMMERS TRANSMITTED | 512 | 1 | 999 | 1 |
UPDATE RATE | 40 | .594(3) | 5200(4) | NA |
START CODES SENT | 0 | ANY | START | CODE |
(1) Maximum with MAB set to 8S , (2) Maximum with break set to 88S, (1 or 2) The Total of break and MAB cannot exceed 49152S . (3) 512 dimmers, 49,144us break, 8S mark, 334S IBT(15 units), 1.454 second IPT (65535 units), (4) 1 dimmer, 88us break, 8us MAB
RECEIVED DMX512 PARAMETERS | |||
FUNCTION | MINIMUM | MAXIMUM | NOTES |
BAUD RATE | 250,000 | as per DMX512 | |
BREAK LENGTH | 65S | - | |
MAB LENGTH | 3S | - | |
NUMBER OF DIMMERS | 1 | 512 | OVFL reported for over 512 dimmers |
BREAK-BREAK TIME | 170S | 3 SEC. | |
TERMINATION | 120 Ohms +/- 5% DC coupled | in'"End of Line' mode |
ACCURACY | ||
PARAMETER | ACCURACY | NOTES |
TIMEBASE & BAUD RATE ACCURACY | +/- 75 PPM | 0 - 70 Degrees C, by design, not tested in production |
TRANSMITTED BREAK JITTER | NEGLIGIBLE | Timebase jitter is the major source of break jitter |
TRANSMITTED MAB JITTER | NEGLIGIBLE | Start code = 0 Break + MAB less than 16.380 mS |
TRANSMITTED MAB JITTER | +/- 4S | Non-zero start code or break + mab time greater than 16,380ms |
DIMMER FRAME JITTER | +/- 2S | |
SCOPE TRIGGER TO BREAK JITTER | NEGLIGIBLE | Timebase jitter is the major source of jitter |
RERC'D BRK,MAB
ACCURACY |
+/- 250nS +/-75PPM (1) | Sum of both errors, rounded as needed for display |
REC'D BREAK TO BREAK | +/-8S | See section 5.2(5) |
INPUT & OUTPUT VOLTAGE AND CURRENT LIMITS | ||
VOLTAGE OR CURRENT | NOTES | |
DMX512-OUT PINS 2&3 MAX VOLTS MAX CURRENT |
+20VDC, -12VDC(2) +/- 100 MA |
Withstanding voltage & current |
DMX512-IN PINS 2&3(1)
MAX VOLTS MAX CURRENT |
+50VDC, -30VDC +/-7 MA |
Withstanding voltage & current |
PIN 4&5 IN or OUT | +/-70 VDC | SCOPE TRIGGER - OFF DOUBLE ENDED CABLE TEST - OFF |
PIN 4&5 OUT | +15 VDC, -5 VDC +/-100 MA |
SCOPE TRIGGER - ON |
(1) In terminated modes, in unterminated modes DMX512-OUT limits apply.
OPERATIONAL ENVIRONMENT LIMITS | |||
PARAMETER | RANGE | NOTES | |
AC Line Voltage Required
North American Units |
85 - 135 VAC
100 - 135 VAC |
100mA | - To operate - To charge fully (1) |
AC Line Voltage Required Europe & Other 230 volt locations |
170 - 270 VAC 200 - 270 VAC |
50mA | - To operate - To charge fully (1) |
AC Line Frequency Required | ~50-60Hz | For either voltage option | |
Humidity | 0%to-95% | Non-condensing | |
Altitude | 0 to 1900 meters | ||
Temperature | 0 to 40 Degrees Celsius |
(1) At line voltages below 110 (220) volts charging time will increase markedly. At 100( 200) volts charging time will be nearly double the 120( 230) volt time.
Return to Goddard Design Co. home page
last updated Dec 26, 1999