Related Manuals for PacComm TINY-2
Summary of Contents for PacComm TINY-2
- Page 1 TECHNICAL REFERENCE MANUAL PacComm Packet Controller Models TINY-2 and MICROPOWER-2...
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Page 2: Table Of Contents
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 TABLE OF CONTENTS INTRODUCTION ................4 Features ................4 NET/ROM and ROSE Compatibility ........... 4 COMPUTER INTERFACING ..............5 RS-232 Port Signals ..............5 Nonstandard RS-232C Serial Ports ........... 6 Serial Port Operation At TTL Levels .......... 7 Serial Data Signal Definitions .......... - Page 3 Transmitter locks in transmit condition ......23 APPENDICES Node Interconnection Cables ..........24 Dual TINY-2/MICRO-2 Node .......... 24 Dual Node, TINY-2/MICRO-2 and TNC-2(00) ....24 Triple Node ..............24 Computer Interfacing Diagrams ..........25 Radio Interfacing Diagrams ............. 26 RS-232 Signal Table ..............27 Bit-Shifted ASCII Character Table ..........
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Page 4: Introduction
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 INTRODUCTION This manual applies to both the TINY-2 and MICROPOWER-2 packet controllers. These units share the same basic design and interface to radios and computer terminals identically. The term TINY- 2/MICRO-2 is used throughout this manual to refer to both units when dealing with components and procedures which are the same for both units. -
Page 5: Computer Interfacing
2 through 8 directly (pin 2 to pin 2, etc.). Pin 1 on the TINY-2/MICRO-2 is the Data Carrier Detect (DCD) signal which goes high (true) when the packet controller is in the "connected" state. This is analogous to the DCD signal on telephone modems, i.e. -
Page 6: Nonstandard Rs-232C Serial Ports
Non-Standard RS-232C Serial Ports NOTE: Some computers which require an external TTL to RS-232 adapter to support an RS-232 se- rial port may be interfaced to the TINY-2/MICRO-2 without the RS-232 adapter unit by using the TINY- 2/MICRO-2 TTL level signals. -
Page 7: Serial Port Operation At Ttl Levels
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. - Page 8 The TNC-2 and PacComm TNC-200, and relates them to the newer 9 pin connectors used on many modem computers and the TINY-2/MICRO-2. Note that connecting a DTE device to a DCE device using either 25 pin connectors or 9 pin connec- tors at both ends of the cable provides a 'straight through' wiring of pin numbers, i.e.
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Page 9: Rs-232C Handshaking Protocol
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 RS-232C Handshaking Protocol The CTS and RTS lines of the TINY-2/MICRO-2 serial port (labeled P4 on the circuit board and RS- 232C on the rear panel) are used by the TINY-2/MICRO-2 firmware for hardware "handshaking" to control the flow of data between the computer and the packet controller. -
Page 10: Radio Interfacing
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 RADIO INTERFACING This section describes how to connect the signal cable between the TINY-2/MICRO-2 and the ra- dio. The interconnection should be planned so as to minimize pickup of stray audio and RF noise by the lines. -
Page 11: Accessory Jack Connection
If the radio has an accessory jack with PTT, transmit audio, and receive audio signals, all connec- tions between the radio and TINY-2/MICRO-2 may be done through this jack. The TINY-2/MICRO- 2 is designed to operate with from 10 to 700 millivolt audio input. This is compatible with the sig- nal level provided by most modern transceivers at the "Fixed Audio Output"... -
Page 12: Hardware Description
Watchdog Timer: The SIO (U14) RTSA (pin 17) provides the signal that ultimately keys the ra- dio transmitter. When the TINY-2/MICRO-2 is transmitting, RTSA goes low, which is fed to a Schmidt trigger gate (U6 pin 9) which turns on the PTT LED and returns a high signal to the gate of a VN10 (FET) transistor (Q2). -
Page 13: Modem Disconnect - J5
To use an external modem, it is necessary to cut the traces between pins 1-2 and 17-18 on the bottom of the TINY-2/MICRO-2 PC board with a sharp knife or MotoTool. If RX Clock is provided by the external modem, then cut 13-14. If CTS is provided, cut 9-10. - Page 14 This signal is used for transmitter activation. It activates the PTT pin of the radio connector via the watch-dog timer. The SIO will pull this output low when the TINY-2/MICRO-2 wants to transmit; otherwise it will remain high. This pin is normally jumpered to pin 6 when the on-board modem is used.
- Page 15 This pin is the received data clock signal derived from the NRZI-to-NRZ converter. This pin is normally jumpered to pin 13 when the on-board modem is used. Pin 15 TINY-2/MICRO-2 Ground Reference This pin ties to the TINY-2/MICRO-2 digital ground at the SIO. Pin 16 Additional Ground Reference Pin 17 Receive Data Input This pin is the received data input to the NRZI-to-NRZ Converter.
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Page 16: Adjustments
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 ADJUSTMENTS Jumper Functions The following table lists the function of each jumper on the TINY-2/MICRO-2 PC board. The nor- mal (Standard jumper setting) positions for each are shown. JP B : Lithium Battery • ON (normal) Lithium battery connected •... -
Page 17: Audio Input Level
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 Audio Input Level The TINY-2/MICRO-2 is designed to operate with from 10 to 700 mV audio input. If you obtain au- dio from the headphone or external speaker jack on the radio, place a shorting block on the pins of JPR (factory default) and adjust the audio level to approximately 20 mV with the aid of a high impedance Voltmeter or oscilloscope. -
Page 18: Modem Receive Bias Adjustment
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 Modem Receive Bias Adjustment Trimpot (R9 100k) is the modem bias adjustment. The factory procedure below is used to adjust the modem bias. It normally results in a value of 2.65 to 2.70 VDC on pin 7 of the TCM3105 mo- dem chip (U16). -
Page 19: Troubleshooting
If you cannot pinpoint the trouble using this set of guidelines, then you must either obtain an oscilloscope, or send the board back to PacComm for repair. If you have an oscilloscope available, the trouble shooting is much easier! The checks made above still apply, but now you can "see"... -
Page 20: Loopback Testing
PWR, CON and STA LEDs lit, followed by the CON and STA LEDs extinguishing a second or so later, and the Voltmeter shows a lot of activity for about ½ second, the TINY-2/ MICRO-2 digital section is operating and attempting to send a sign on message out the serial port. -
Page 21: Step 2: Power Supply
DIP switches, jumper pins, or software commands depending on the com- puter terminal in use. The above settings are the default sign-on settings stored in the TINY-2/ MICRO-2 EPROM. Perform a hard reset by pressing the power switch OFF then ON (out then in). -
Page 22: The Controller Won't Accept Commands
If other stations seem unable to decode your packet transmissions, it is possible that your trans- mitter is being overdriven. Listen to the sound of your TINY-2/MICRO-2 transmissions on another receiver. Extremely weak signals indicate inadequate modem output. Refer to the Transmit Level Adjustment Procedure. -
Page 23: Uncopyable Received Packets
R10 to a lower value between 10 and 100 Ohms. Transmitter locks in transmit condition The TINY-2/MICRO-2 is protected against PTT malfunction by a watchdog timer on the keying line. However, if unshielded, improperly grounded cabling is used to feed the transmitter key line, and other signal cables, RF energy can get back into the packet controller and lock up the keying tran- sistor. -
Page 24: Appendices
These diagrams are intended for use with NET/ROM, ROSE and other network EPROMs. If these diagrams do not agree with those suggested by the network software manual, use those provided by the software manual, modified as necessary for the TINY-2/MICRO-2 9 pin connector. Dual TINY-2/MICRO-2 Node... -
Page 25: Computer Interfacing Diagrams
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 Computer Interfacing Diagrams Atari Joystick Port to TINY-2/MICROPOWER-2 TTL Port Tandy/Radio Shack Color Computer to TINY-2/MICRO-2 RS-232 Port Commodore VIC-20/C-64/C-128 User Port to TINY-2/MICRO-2 TTL Port Apple Macintosh Computers - 25 -... -
Page 26: Radio Interfacing Diagrams
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 Apple II Color Computer TINY-2/MICRO-2 RS-232 2 –––––––––––– 2 3 –––––––––––– 5 4 –––––––––––– 3 Tandy/Radio Shack Color Computer Radio Interfacing Diagrams ICOM 8-pin (IC-27 etc.) Mic Jack Pinout Data IN Data OUT (before Squelch) -
Page 27: Rs-232 Signal Table
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 RS-232 Signal Table The EIA RS-232C Standard The Electronic Industries Association (EIA) RS-232C Standard defines the interfacing between data terminal equipment and data communication equipment employing serial binary data interchange. Electrical signal and mechanical aspects of the interface are well specified. The complete RS-232C interface consists of 25 data lines. -
Page 28: Bit-Shifted Ascii Character Table
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 Bit-Shifted ASCII Character Table The characters of AX.25 callsigns are standard 7 bit ASCII characters shifted to occupy the upper 7 bits of the byte. The following table contains the hexadecimal values for the characters of the al- phabet and digits 1 - 0 bit shifted one place for use in callsign definitions in packet controller EPROMs. -
Page 29: Schematic
TINY-2/MICRO-2 Technical Ref., 2. Ed 1989 - 29 -...