The TQMC400 is a VITA 93.0 compatible Small Form Factor Mezzanine Card (QMC) offering 4 UART channels with multiprotocol transceivers. Each channel can be programmed to operate as an RS232, RS422/RS485 full duplex or RS485 half-duplex interface.
Each RS232 channel supports RxD, TxD, RTS, CTS, DTR, DSR, CD, RI and GND. RS422 and RS485 full-duplex supports a four wire interface (RX+, RX-, TX+, TX-) plus ground (GND).
RS485 half-duplex supports a two wire interface (DX+, DX-) plus ground (GND). On-chip switchable termination of 120Ω is provided for the RS422/RS485 interfaces.
Selectable data rates are up to 1 Mbps for RS232 mode and 20 Mbps for RS422/RS485 half-duplex and full-duplex mode. Additionally, a reduced slew rate mode with lower EMI provides data rates with max. 250 kbps for RS232 and max. 500 kbps for RS422/RS485.
Each channel has 256 byte transmit and receive FIFOs to significantly reduce the overhead required to provide data to and get data from the transmitters and receivers. The FIFO trigger levels are programmable. The UART offers readable FIFO levels.