The 7I50 is a 24 I/O SPI expander for use with MESAs Anything I/O cards. The 7I50 has 24 bidirectional logic level I/O pins and connects to a SPI interface. The 7I50 can use a TTL level SPI interface or differential SPI. One Anything I/O connector can drive six 7I50s for a total of 144 I/O points pe