ATG429EBPOperationManual
3‐2
June4,2015
Rev.A2
3.1.3.1.1 TRANSMISSION RATES
The word rate for each of the ten TX Slots can be set independently. The repetitive word rate can be as
low as 4 msec or as long as 59998 msec. On label entry the word rate defaults to the minimum word rate
defined in the ARINC 429-11 specs. The 429EBP also has the capability of transmitting words only on
user command (SINGLE SHOT). Each slot can be programmed independently for this mode by
programming the word rate for that slot to 1ms (SNGL SHOT). The user then presses the SINGLE SHOT
key on the front panel whenever he (she) wants to transmit all words programmed for single shot. Each
subsequent press of this key will retransmit all words programmed for single shot mode. This mode will
not interfere with any words that have been programmed for repetitive transmission. The transmitter
automatically insures at least a 4 bit time (Low Speed) separation between adjacent words.
NOTE: The ten TX slots are priority weighted. Slot ten has the most priority and slot one has the least.
The advantage of this method is that it allows synchronized bursts of words. The disadvantage is that
words programmed into lower numbered slots than a slot with a 4ms word rate (fastest rate possible) will
not be transmitted. e.g. If slot ten is programmed to a 4ms word rate then the words in slots one through
nine will not be transmitted.
3.1.3.1.2 PROTECTED MODE
The transmitter section may be placed into a `PROTECTED' mode of operation. This mode protects the
user entered parameters from changing when the unit is powered off. When power is restored to the unit
it will resume operation where it was at when the unit was powered off. If 'Protect' mode is off then the
unit will clear the transmitter section on power up. The unit will stay in the selected mode until changed by
the user, even if the unit power is cycled.
3.1.3.1.3 DATA SLEWING
The data for most labels with engineering definitions can be `SLEWED'. This means that the data will
dynamically change value according to user defined parameters. There will be 4 slew screens in the data
mode for any label with slew capability. The first screen is a `SLEW' screen that defines the amount of
change in data. When this parameter is set to `0' (default) then no slewing will occur. The second screen
is the `MAX' screen which defines the upper limit that the data is allowed to slew to. The third screen is
the `MIN' screen which defines the lower limit that the data is allowed to slew to. Either parameter may
be positive or negative (dependent on ARINC definition for the label) but the `MAX' parameter MUST be
larger then the `MIN' parameter. Note that only bits 28 - 17 of the limits will be used in the limit check. All
other bits are ignored and will be truncated upon user entry of new limit values.
The fourth screen turns the `ALT' (Alternate) mode on and off. If this mode is on, the data will slew to the
limit in the direction it is going. When the limit is reached, the data will be set to that limit and then slew to
the opposite limit. When this limit is reached, the data will again reverse itself. If `ALT' is off, the data will
slew in the direction entered in the `SLEW' parameter (positive or negative) to the limit and then reset to
the value defined for the opposite limit (data wraps around). NOTE: Any ARINC BCD type words will only
slew by 1 in the negative direction regardless of the SLEW value setting.
3.1.3.2 RX MODE
The receiver has the capability of receiving and storing up to 4096 (8192 in `DATA ONLY' mode) high or
low speed 32 bit words in ARINC 429 or 419 RZ format. There are three mutually exclusive receiver
modes of operation. Each mode has a screen that shows the count of words received, the label and
description, or the data field currently selected.
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