TDK Module blu2i User Manual

TDK Module blu2i User Manual Manual pdf 5 page image

Application Interface2The blu2i Module is equipped with a 40-pin 0.5mm pitch board to boardconnector that connects to the application platform. Electrical andmechanical characteristics of the board-to-board connector are specifiedin Chapter 3.• Serial interface (see Section 3.0)• Electrical specification of the interface (see Section 3.1)2.1 Serial InterfaceUART_TX, UART_RX, UART_RTS and UART_CTS form a conventionalasynchronous serial data port. The interface is designed to operatecorrectly when connected to other UART devices such as the 16550A.The signalling levels are nominal 0V and 3.3V and are inverted withrespect to the signalling on an RS232 cable. The interface isprogrammable over a variety of bit rates; no, even or odd parity; stop bitand hardware flow control. The default condition on power-up is pre-assigned in the external Flash. Two-way hardware flow control isimplemented by UART_RTS and UART_CTS. UART_RTS is an outputand is active low. UART_CTS is an input and is active low. Thesesignals operate according to normal industry convention.By writing different values to the S register the UART_RI can becontinuously polled to detect incoming communication. The UART_RIsignal serves to indicate incoming calls.UART_DSR is an active low input. It should be connected to DTR outputof the host. When the module is running in high speed mode (Seedefinition for S Register 512), this pin should be asserted by the host toensure connection is maintained. A deassertion is taken to mean that theconnection should be dropped, or an online command mode is beingrequested.The module communicates with the customer application using thefollowing signals:RS-232• Port /TXD @ application sends data to the module’s UART_RXsignal line• Port /RXD @ application receives data from the module’sUART_TX signal line5 of 36