PacComm TINY-2 Technical Reference Manual

TINY-2/MICRO-2 Technical Ref., 2. Ed 1989
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Serial Port Operation At TTL Levels
The TINY-2/MICRO-2 packet controller is designed to operate with computers which have a TTL
level serial port without requiring the use of an RS-232C adapter. This includes such popular com-
puters as the Commodore VIC-20, C-64, and C-128. TTL signals are routed through an 8 pin con-
nector on the rear panel. TTL signal levels must be greater than +2.4 Volts in one state and less
than +.4 Volts in the other state.
Use caution in connecting the TTL cable to insure that pin one of the cable is attached to pin one
of the connector. Pin one is clearly marked on the rear panel of the controller. Pin one of the cable
connector is marked with a red stripe, Be sure to observe this marking both in constructing and at-
taching the cable.
TTL serial port signals used by the TINY-2/M1CRO-2 controller.
P3
Signal Name
Description
1
2
3
4
5
6
7
8
Receive Data
Carrier Detect
Frame Ground
Clear to send
Transmit Data
Signal Ground
Request to send
No Connection
Serial data to computer from the TlNY-2/MICRO-2
Goes high when connection exists
Common ground for case and data lines
Computer Signal Clearing Controller to send data
Serial data to the TINY-2/MICRO-2 from computer
Common ground for both data lines and case
Controller signal to computer when data is ready
Serial Data Signal Definitions
This section describes the pins used on the packet controllers serial port connectors. Since the pins
are defined with respect to the Data Terminal Equipment (DTE) (computer) end of the circuit, and
the packet controller is wired as Data Communications Equipment (DCE) (modem), some standard
pin names appear to be the reverse of the packet controller function. A complete RS-232 signal ta-
ble appears in the Appendices.
Serial Port Pin Functions
Frame Ground (FG) is provided for attachment to the chassis of the packet controller and the
chassis of the attached computer terminal. This is common to the signal ground on the TINY-
2/MICRO-2.
Transmit Data (TXD) is an input line to the packet controller on which the attached computer
terminal device sends data.
Receive Data (RXD) is an output line from the TINY-2/MICRO-2 on which it sends data to the
attached computer terminal device.
Request to Send (RTS) is an input to the packet controller signaling that the attached comput-
er terminal device is ready to accept data from the TINY-2/MICRO-2. This line is used for hard-
ware flow control.
Clear To Send (CTS) is an output from the packet controller signaling the attached computer
terminal device to send data to the TINY-2/MICRO-2. This line is used for hardware flow con-
trol.
Data Set Ready (DSR) is an output from the packet controller telling the attached computer
terminal device that the packet controller is operational. On the TINY-2/MICRO-2 this pin is
tied high (ready).
Signal Ground (SG) is the common, or return, path for all signals between the TINY-2/MICRO-2
and the attached Computer terminal device. It is common with the frame ground.

PacComm TINY-2 Specifications

General

Brand	PacComm
Model	TINY-2
Category	Controller
Language	English