The HI-3596, HI-3597, HI-3598 and HI-3599 from Holt Integrated Circuits are silicon gate CMOS ICs for interfacing eight ARINC 429 receive buses to a high-speed Serial Peripheral Interface (SPI) enabled microcontroller. Each receiver has user-programmable label recognition for up to 16 labels, a four-word data buffer (FIFO), and an on-chip analog line receiver. Receive FIFO status can be monitored using the programmable external interrupt pins, or by polling the status register. Other features include the ability to switch the bit-signifiance of the ARINC 429 label, and to recognize the 32nd received ARINC bit as data or a parity flag. Versions are available with different input resistance values to provide flexibility when using external lightning protection circuitry.
The Serial Peripheral Interface minimizes the number of host interface signals, providing a small footprint device which can be interfaced to a wide variety of industry-standard microcontrollers supporting SPI. Alternatively, the SPI interface may be controlled using four general purpose I/O port pins from a microcontroller or custom FPGA. The SPI and all control signals are CMOS and TTL compatible and support 3.3V or 5V operation.
The HI-3597 and HI-3599 are identical to the HI-3596 and HI-3598 except not all pins are available. This allows a minimum package footprint to be achieved with only slightly less hardware flexibility.