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Keyboard/mouse interfaces, Keyboard interface – Ampro Corporation AMPRO Single Board Computer MightyBoard 821 User Manual

Page 24

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Chapter 3

Hardware

20

Reference Manual

MightyBoard 821

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.

6

8

CTS3*

RX3+

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+ – 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

(COM4)

DCD4*

Data Carrier Detect 4 – Indicates external serial communications
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

RX4-

Receive Data 4 – Serial port 4 receive data in

RX4- – If in RS485 or RS422 mode, this pin is Receive Data 4 -.

14

7

RTS4*

TX4+

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+ – If in RS485 or RS422 mode, this pin is Transmit Data 4 +.

15

3

TXD4

TX4-

Transmit Data 4 – Serial port 4 transmit data out

TX4- – If in RS485 or RS422 mode, this pin is Transmit Data 4 -.

16

8

CTS4*

RX4+

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+ – 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

Table 3-5. Serial 3 and 4 (COM3 and COM4) Interface Pin/Signal Descriptions (J15)