Ampro Corporation MightyBoard 821 manual Keyboard/Mouse Interfaces, Keyboard Interface

Chapter 3				Hardware
Table 3-5. Serial 3 and 4 (COM3 and COM4) Interface Pin/Signal Descriptions (J15)
	6	8	CTS3*	Clear To Send 3 – Indicates external serial communications device is
				ready to receive data. Used as hardware handshake with RTS3 for
				low level flow control.
			RX3+	RX3+ – If in RS485 or RS422 mode, this pin is Receive Data 3 -.
	7	4	DTR3*	Data Terminal Ready 3 – Indicates Serial port 3 is powered,
				initialized, and ready. Used as hardware handshake with DSR3 for
				overall readiness to communicate.
	8	9	RI3*	Ring Indicator 3 – Indicates external serial communications device is
				detecting a ring condition. Used by software to initiate operations to
				answer and open the communications channel.
	9	5	GND	Ground
	10	NC	NC	Not connected
	11	1	DCD4*	Data Carrier Detect 4 – Indicates external serial communications
		(COM4)		device is detecting a carrier signal (i.e., a communication channel is
				currently open). In direct connect environments, this input will be
				driven by DTR4 as part of the DTR4/DSR4 handshake.
	12	6	DSR4*	Data Set Ready 4 – Indicates external serial communications device is
				powered, initialized, and ready. Used as hardware handshake with
				DTR4 for overall readiness to communicate.
	13	2	RXD4	Receive Data 4 – Serial port 4 receive data in
			RX4-	RX4- – If in RS485 or RS422 mode, this pin is Receive Data 4 -.
	14	7	RTS4*	Request To Send 4 – Indicates Serial port 4 is ready to transmit data.
				Used as hardware handshake with CTS4 for low level flow control.
			TX4+	TX4+ – If in RS485 or RS422 mode, this pin is Transmit Data 4 +.
	15	3	TXD4	Transmit Data 4 – Serial port 4 transmit data out
			TX4-	TX4- – If in RS485 or RS422 mode, this pin is Transmit Data 4 -.
	16	8	CTS4*	Clear To Send 4 – Indicates external serial communications device is
				ready to receive data. Used as hardware handshake with RTS4 for
				low level flow control.
			RX4+	RX4+ – If in RS485 or RS422 mode, this pin is Receive Data 4 +.
	17	4	DTR4*	Data Terminal Ready 4 – Indicates Serial port 3 is powered,
				initialized, and ready. Used as hardware handshake with DSR4 for
				overall readiness to communicate.
	18	9	NC	Not connected
	19	5	GND	Ground
	20	NC	NC	Not connected

Note: The shaded area denotes power or ground. Signals are listed in the following order: RS232 followed by RS485/RS422

Keyboard/Mouse Interfaces

Keyboard Interface

The Super I/O chip (W83627HF) provides the signal lines for the PS/2 keyboard through the keyboard connector (J1A), which is fully PC/AT compatible.

20 Reference Manual MightyBoard 821