ARINC 429

Each ARINC 429 channel has a large FIFO buffer (32 ARINC 429 words) that can provide a service request when the FIFO is empty, half-full, or full. The speed of each channel may be independently set for high or low. Non-standard speeds may be obtained through a programmable divider and/or a custom clock. Each receive channel has independent label and SDI filtering. When enabled, received words are rejected if they do not match the specified SDI and one of the 16 programmable label filters. Each transmit channel has a gap timer that simplifies the programming required to maintain label repetition rates. After all the words in the FIFO have been transmitted, the gap timer counts out the specified number of bit-times before a new group of words can be transmitted, thus maintaining an exact schedule. Each ARINC 429 channel has an LED that blinks when there is activity on that channel.

Discretes

The PM429-1 is available with up to eight input and four output discretes. The input discretes are factory-configured to the desired circuit and threshold voltage. A variety of series and shunt configurations (open/ground, voltage/ground, and voltage/open) are available. In addition to analog filtering, inputs are debounced through a programmable digital circuit. Each input discrete may be programmed to issue a service request on the positive and/or negative edge of the input signal. Output discretes are under host control and have open-collector circuits with optional pull-up resistors.