SDLC End-Of-Frame Request to Send Hold Technique
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
Modems using an EIA RS232c Interface require a Request To Send (RTS) signal to be held active for a minimum number of byte times after a transmit frame has been completed. A technique is described to allow Data Terminating Equipment (DTE) to perform this function without knowing the line baud rate. Data Terminating Equipment (DTE) and Data Circuit-terminating Equipment (DCE) use EIA RS232c interfaces to provide remote communications. Request To Send (RTS) is one of the control lines used in the interface to allow the DTE to inform the DCE that there is data to be transmitted. There are specific timing requirements put on the DTE by the DCE to guarantee proper operation. An efficient method of meeting those timing requirements without increasing system loading or complexity is described.