Quatech MPAP-100 user manual External Connections

19 External Connections

The MPAP-100 is configured as a Data Terminal Equipment (DTE) device, meeting the RS-232-D standard using a DB-25 male connector. There is no DCE version available.

The control signals the DTE can generate are Request To Send (RTS) and Data Terminal Ready (DTR). It can receive the signals Carrier Detect (DCD), Clear to Send (CTS), and Data Set Ready (DSR). All the control signals are controlled through channel A of the SCC, with the exception of the DSR signal, which is received on the DCDB pin on channel B. (The SCC has no actual DSR inputs.)

The DTE can transmit its transmit clock (TCLK) from the TRxCA pin of the SCC, or receive TCLK on the same pin. The DTE can also receive its receive clock (RCLK) on the RTxC pins on channels A & B of the SCC, or can generate RCLK using the TRxCB pin. TCLK and RCLK can also be internally sourced from the channel A baud rate generator.

Figure 1 shows the DTE clock configuration. On the left are the SCC clock pins and the clock enable bits from the Communications Register. On the right are the signals at the DB-25 connector. Figure 2 illustrates the connector pinout.

RTxCA

(RCLK)

RTxCB

TRxCB

RCKEN

TRxCA

(TCLK)

RXCLK (DCE)

RXCLK (DTE)

TXCLK (DTE)

TXCLK (DCE)

TCKEN

Figure 1 --- MPAP-100 Clock Configuration