MFJ MFJ-47A, MFJ-47C, MFJ-47B User Manual

MFJ-47 A/B/C

MEMORY EXPANSION UPGRADE

Thank You for purchasing the MFJ-47A/B/C Mailbox Memory Expansion for your MFJ TNC2. The MFJ-47 is for MFJ TNC2 models such as, MFJ1270/1270B/1274/1270BT/1274T). The most recent firmware is supplied the the MFJ-47 Mailbox Memory Expansion boards. The firmware eprom is wrapped in tin foil for electrostatic protection. You will need to take the necessary precautions when installing the firmware eprom in the MFJ-47 Mailbox MemoryExpansion board. Documentation for the firmware upgrade is supplied.

You will notice that some sockets on the memory expansion are not populated (U413, U422 & U425) when received. These sockets will bepopulated with ICs to be transferred from the motherboard.

The various versions memory expansion boards are as follows:

ModelNo.	SRAM Size	MFJ TNC2

MFJ-47A	32K	MFJ-1270/1270B/1274
MFJ-47B	128K	"
MFJ-47C	512K	"

The extra memory provided by the expansion boards are dedicated solely for the use of the packet mailbox. The firmware of the TNT does not allocate this additional memory to other operations. Battery back up for the memory board is supplied from the mother board.

MFJ TNC2		MEMORY EXPANSION UPGRADE

MEMORY BOARD INSTALLATION

In this installation you will be required to remove three ICs from the mother board and transfer them to the memory board. Please handle the ITs carefully and make note of the IC number and its orientation.

Throughout this installation instruction we will use "TNC" in reference to all of the MFJ TNC2 models. MFJ-1270/127OB/1274. Please read and perform the following procedure very carefully:

l.Disconnect all of the cables from the TNC. including power. radio and computer.

2.Remove the top cover of the TNC by removing the four (4) screws on the sides the unit. Then lift the cover off.

3. Remove the jumper off of JMP5. This takes the lithium battery out of the circuit. If your TNC has a MFJ-2400 modem installed. remove it. Set it aside. it will be re-installed later.

NOTE: When removing ICs from your TNC ensure that y ou do not bend or break any of the pins.

4. Using a small flat tip screwdriver remove the following ICs from your TNC. Please take note as to the orientation of the ICs as you remove them.

U13--	74HC4066	U25--	NEC 43256-IOL or Equiv.
U22--	ZO840004PSC Z80 CPU	U23--	SYSTEM EPROM

5. Install the ITs which were removed from your TNC in the above step. Take note as to the orientation of the IC. Match up the NOTCH on the IC to the NOTCH on the IC socket on the expansion board. Refer to Figure 2 parts layout diagram for proper installation of the ICs.

MFJ TNC2	MEMORY EXPANSION UPGRADE

Install the ITs removed from the mother board to the memory board as follows:

74HC4066	(U13)	in	socket IC-413
43256	(U25)	in	socket IC-425
Z80 CPU	(U22)	in	socket IC-422

A new EPROM with the new firmware is packaged with the memory kit. You will install the new EPROM at U23 on the mother board. Be sure to orient the new EPROM the same way in which you removed the old one. In order to do this properly you must first position the TNC so the front panel is facing you. this is very important. Then locate the NOTCH on the new EPROM. Now install the new EPROM with the NOTCH pointing to your left.

7. Check and make sure that there no IC pins are bent under the IC itself. Check and make sure that no IC pins are broken off. and that all IC pins are inserted in the IC socket. Do this before proceeding beyond this point.

8.Set the memory board aside for now.

9.Please refer to Figure 1 when performing this step. Using a small phillips screwdriver remove the PC hold-down screw in the left rear

corner of the TNC mother board, this is refered to as HOLE "A". Do not let this screw out of your sight, you'll be using it here shortly.

10. Take the l/2" hex spacer supplied and install it in HOLE A, as noted in Figure 1 in this instruction. This is the same place where you removed the screw in Step #8, and tighten it down. This is an aluminum spacer DO NOT OVER TIGHTEN it, you will STRIP the

THREADS.

MFJ TNC2 MEMORY EXPANSION UPGRADE

11. Now with the memory board in one hand, plug the free end of the 40pin ribbon cable into the IC socket labeled U22 (please refer to Figure l; this is the same one which you removed the Z80 CPU from earlier in this procedure) on the mother board. Be sure to orient the blue connector so that pin 20 and 21 on the b lue connector are oriented to the right side of the IC socket, (with the front panel of the TNC facing toward you). You will need to twist the cable slightly. Ensure that you leave the CN402 pigtail free and clear, do not let it become pinched or caught up underneath anything.

NOTE: If you do not have an MFJ-2400 board installed in the TNC skip to step 14.

12.If you have an MFJ-2400 modem installed position the 40-pin cable, so the cable is not going to be pinched by the mounting stud for the MFJ-2400 modem.

13.Now you can re-install your MFJ-2400 modem. Be sure that you do not pinch any of the wires of the 40-pin ribbon cable or the CN402 pigtail when you tighten the MFJ-2400 down. This will cause problems with both the MFJ - 2400 and the memory board. So be sure and double check this.

14.Find the original hold-down screw which you removed from the TNC mother board earlier. Secure the memory board to the l/2" spacer which you installed earlier. Again this an aluminum spacer, DO NOT OVER-

TIGHTEN it! You will STRIP the THREADS.

15. Take note of the location of the NOTCH on CN402. Now plug CN402 into the IC socket labeled U13 (socket which the 74HC4066 ryas removed earlier) on the TNC mother board. Please refer to either Figure l. Plug it in so the NOTCH is pointing toward the lithium batten. Make sure it is firmly in place!

MFJ TNC2		MEMORY EXPANSION UPGRADE

16.Remove the paint (if any) from around the mounting holes on the outside of the chassis and the inside of the cover. This can be done with either light sandpaper or a knife blade. This will eliminate any

EMI from the TNC caused by the additional large ribbon cable. This concludes the installation of the mailbox memory expansion board. However. before you start putting things back to together double check ever thing you have already done.

Final Inspection

Before closing up the TNC it would be best at this time to do a final inspection of your installation. Please check all of the following:

I . Check all connections to ensure that they are all secure.

2.Make sure that there are no pins bent or broken on any of the IC's or connectors installed in this procedure.

3.Make sure that there are no wires pinched or caught up under any of the screws. circuit boards or connectors.

4.Last but not least give your TNC one last physical look over, for any debris or foreign matter on the main PC.

If all of the above checks out then you can re-install the battery jumper JMP5. Connect the computer cable to the TNC apply power and see if you can obtain the TNC's sign-on messagc . If not, then go back and double check the entire installation procedure. If the TNC signed on properly, install the cover.

After properly installing the memory board. reconnect your TNC to your radio and computer. If the TNC signed your installation is successfully. Follow the instruction given by the upgrade documentation to operate your mail box.

RAM chips can be

MFJ TNC2		MEMORY EXPANSION UPGRADE

RAM EXPANSION AND FIRMWARE EPROM UPGRADE

The RAM on each version of the MFJ-47 Mailbox Memory Expansio board is upgradable. Either version of the MFJ-47 Expansion board can us either 32K, 128K. or 512K RAM IC. When interchanging the RAM IC pleas follow the MFJ-47 instruction manual for jumper positions. The RAM IC o the MFJ-47 Mailbox Memory Expansion is changed simply by replacing IC42 on the memory board and relocate the jumper at J401

header. Refer to Figure 2 and the following chart. ordered from MFJ Enterprises, Inc.

ITEM No	RAM TYPE		J401 POSITION
MFJ-45A	432456LP-10	(32K)	The (2) inside most pins
MFJ-45B	431000LP-10	(128K)	The (2) middle pins
MFJ-45C	8512LP-10 (512K)		The (2) outside most pins

There is only one version of the firmware EPROM upgrade for the MFJ TNC First of all the firmware version enclosed with the MFJ-47 upgrades wi function in MFJ-1270/1270B/1274 with the MFJ-47 installed. The firmwar version enclosed with the MFJ-47 upgrades will also function in the MFJ 1270C and MFJ-1274C TNCs. When upgrading the EPROM remember t request the EPROM upgrade. MFJ-40CX.

Secondly. there is another firmware version for the MFJ1270/1270B/127 without the MFJ -47 installed. MFJ-40A. B, or C. When upgrading the EPRO in an MFJ-1270/1270B/1274 TNC without the MFJ-47 installed remember t request the EPROM upgrade. MFJ40C.

MFJ TNC2

MEMORY EXPANSION UPGRADE

RELEASE 1.1.4 NOTES:

FIXES

∙Transmitted I-frames under Level 2 Version 2 did not have their P bits set at the appropriate times. In fact. they never had their P bits set. This has now been fixed. The last I-frame of a multiple I-frame transmission has its P bit set.

∙A mistake in the protocol state table was fixed.

∙bbRAM scanning now checks all ten possible connection control structures

(instead of just the first one).

CHANGES

∙AX25L2V2 defaults to the ON position.

∙Major change made to AX25L2V2 handling. If retie limit is exceeded. or the TNC receives a "disconnected" response to a poll. the connection is ended

The old method (and the one proscribed) is fraught with problems for automated stations that can not recover without an indication of loss of the connection.

The PERMCONcontrol will replace the functionality of this aspect of AX25L2V2 which was removed.

ENHANCEMENTS

∙32K of RAM is now expected. Virtually all of the new space is used t o enlarge existing queues within the TNC, yielding greater performance especially at faster RF data rates. and making the onboard message buffer capability a bit more useful.

∙The MCOM command decodes all control fields.

For I and S frames, sequence number information is also presented. Frames compatible with the AX.25 Level 2.0 standard are also decoded as to the state of the Command/Response (C/R) and Poll/Final (P/F) bits.

MFJ TNC2

MEMORY EXPANSION UPGRADE

Ex: WA7GXD>KV7B : Hi

Dan,

WA7GXD>KV7B : have you been on EIES lately?

KV7B>WA7GXD <RR R F R2>

KV7B>WA7GXD :

I was just thinking about that. I heard that @(username)

made some real

unbelievable comment on it!

WA7GXD>KV7B <RR R F R2>

WB2SPE>KV7B <C>

KV7B>WB2SPE <DM>

KV7B>WA7GXD :

Good conditions now

WA7GXD>KV7B <RR R F R3>

WA7GXD>KV7B :

Yes @(username) did. It was quite remarkable.

And so on. See Chapter 9 Table 9-1 in Four TNC 2 manual for a breakdown of the control field codes. For complete information on the A X . 25 Level 2 Version 2.0 Protocol, please refer to the ARRL AX.25 Protocol Specification document. available from ARRL.

	MFJ TNC2	MEMORY EXPANSION UPGRADE
NEW COMMANDS FOR 1.1.4
CBELL ON:OFF		Default: OFF
Parameters:
ON Connect bell enabled OFF
Connect bell disabled

This command is used t o control whether an ASCII $07 (BELL) character is sent as part of the connected message.

When set ON. the bell character immediately precedes the asterisk portion of the connected message, e.g.:

<BELL>*** Connected to: <callsign>

CM5GDISC ON:OFF

Default: OFF

Parameters:

ON Automatic disconnect enabled OFF

Automatic disconnect disabled

This command controls whether or not the 1F7 TNC will initiate a disconnect sequence after it is connected to.

If CMSG is OFF, or CTEXT has no connected text, the TNC initiates a disconnect immediately upon receiving information or acknowledgment frames from the other station.

If CMSG is ON end CTEXT contains some text information, the TNC initiates a disconnect after the packet containing connect text (CTEXT) is acknowledged.

MFJ TNC2	MEMORY EXPANSION UPGRADE

This command may be useful to bulletin board operators or others with a need to send a short message. confirm its receipt. and disconnect.

LFIGNORE ON:OFF

Default: OFF

Parameters:

ON TNC will ignore <LF> characters. OFF

TNC will respond to <LF> characters.

This command controls whether TNC 2 responds to ASCII Line Fee (<LF> $OA) characters or ignores them in command and converse modes.

When turned on_ line feeds are totally ignored except in transparent mode.

New HEALTH Counters

BBfailed n: Counts number of times bbRAM checksum was in error.

TXQovflwn: Counts how many times frames were discarded because th outgoing frame queue was too small.

MFJ TNC2

MEMORY EXPANSION UPGRADE

RELEASE 1.1.5 NOTES

FIXES

∙Release l. l.4 suffered from a spurious condition where the HDLC transmitter would time out. When this happened TXQOVFLW would typically show a non-zero count. Release l.l.5 incorporates an HDLC transmitter timeout feature to capture and recover from the timeout error.

•DWAIT operation has been fixed.

NEW COMMANDS FOR 1.1.5

BBSMSGS ON:OFF

Default: OFF

This command controls how the TNC displays certain messages in command and CONVERSE modes. The messages affected are described

below

MESSAGE	EFFECT WHEN BBSMSGS ON
***CONNECTED to xxxx	A newline is added just before"***"
***DISCONNECTED	"
***retry limit exceeded	"
***xxxx Busy	"
***FRMR sent	"

* * * FRMR rcvd" ***Connect request:xxxxThis message is omitted.

The BBSMSGS command is primarily useful for host operation. Primarily with WORLI and like bulletin board systems that require link status messages to begin in the first output column.

The connect request message is omitted during BBSMSGS mode. This should be most useful for preventing corruption of messages when forwarding with small frames.

TXTMO: Counter

Default: 0

TXTMO is a new addition to the TNC health-group. This register may accumulate counts as the TNC successfully recovers from HDLC transmitter timeouts. This is not a useful command for the majority of the users.

MFJ TNC2

MEMORY EXPANSION UPGRADE

RELEASE 1.2.6 NOTES

ENHANCEMENTS

1.KISS enables the MFJ-1270B/1274 to act as a modem for a host computer. Turning KISS on allows the MFJ-1270B and MFJ-1274 to run programs such as TCP/IP. MSYS and other programs which used the Serial Link Interface Protocol (SLIP).

2.Weather FAX reception is now possible for users who use IBM and compatibles. Macintosh or Commodore C64/128 computers. With these computer. to receive weather FAX you must use the MFJ-1287B starter pack for the Macintosh computer. the MFJ -1284/1249 starter pack for the IBM and compatibles or the MFJ-1282 for commodore C64/128.

3.The MNonax25 command is installed. When this command is turned ON. the display of non -AX.25 packets is inhibited.

KISSCOMMANDOPERATION

KISS ONOFF

Default: OFF

Parameters:

ON Serial Line Interface protocol (SLIP) is used between the TNC and the attached co mputer. The TNC executes a very limited instruction set, arbitrating channel access only and depending on the computer to handle all Level Two and higher protocol issues.

OFFThe TNC operates using the commands and messages documented herein. This is the normal mode of operation.

This command is used to enter the "KISS" mode for operation with various experimental protocols. KISS is used with intelligent host computers. The most popular use has been in conjunction with the KA9Q TCP/IP networking software.

To operate KISS, enter the command KISS ON, then the command RESTART (NOT RESET!). The CON and STA LEDs will flash three times when initially activated. This command will then have effect for subsequent power on/off cycles.

MFJ TNC2

MEMORY EXPANSION UPGRADE

MFJ MFJ-47A, MFJ-47C, MFJ-47B User Manual

MFJ TNC2

MEMORY EXPANSION UPGRADE

MFJ TNC2	MEMORY EXPANSION UPGRADE
Note: The TNC	will only return type 0 frames (received information).

Thus, the computer cannot interrogate the TNC to find the values of the other command types.

WEATHER FAX OPERATION

To receive Weather FAX with the TNC 2 you will need to have software for your computer to receive the picture and print it on the computer screen or to save the pictures to disk. The MFJ-1284 or MFJ-1289 Starter Pack for the IBM and compatibles computer. MFJ-1287 for the Macintosh or the MFJ-1282 for Commodore C64/128 allows you to print Weather FAX pictures to screen in near real time and to save Weather FAX pictures to disk. Weather FAX pictures saved on disk can be sent to your printer, or recalled to screen at any time. The TNC-2 FAX mode can receive FAX pictures transmitted in the 120 line per minute (2 linc/sec) format such as Weather FAX. Weather FAX are received by the TNC 2 in the 2-level format. Multi-gray level FAX and other FAX formats are not supported by the TNC-2,

FAX Frequencies

Most Weather Fax transmitting stations are usually found on the HF bands. Weather FAX stations are generally upper sideband. Some of these stations maintain a regular schedule. The frequencies of some Weather FAX stations are:

3,357.00 4,268.00 4,975.00 6,946.00 10,865.00 12,125.00 20,015 Other FAX Frequencies and the station location are listed in the following chart. These frequencies were obtained from Popular Communications Magazine:

MFJ TNC2

MEMORY EXPANSION UPGRADE

Receiving Weather FAX

Connect an I -W Radio to the TNC 2 as described in the Radio connection of the TNC 2 instruction manual. Set -up the TNC 2 for VHF operation.

From the cmd: command mode, the TNC 2 can be set to Weather FAX mode by typing:

FAX<CR>

At this point you will want to set your computer program to start printing the Weather FAX picture on the screen. Do this according to the instruction manual supplied with the software.

Once the program is properly set. set the audio output of your radio to normal volume. Tune your radio to a desired frequency. If you are not familiar with recognizing FAX signals. you may want to select one of the weather FAX frequencies listed above. Weather FAX is usually transmitted at 1200 lines per minute. This is a horizontal scanning rate of 2 lines per second. So by listening to the scanning rate. you can determine if the TNC 2 is capable of receiving that particular FAX signal.

After tuning in the desired FAX frequency. tune the radio so that the DCD LED remains lit. Now observe the TUNING INDICATOR of the TNC2 while fine tuning your radio (for TNC 2 with tuning indicator only). You will notice that with each scan the tuning indicator will move toward the center. Tune the radio so that the tuning indicator is centered at the end of each FAX scan. Once you achieve this, the FAX signal is tuned in and the TNC 2 is ready to decode the FAX signal.

Proper tuning of the FAX signal is very important for successful Weather FAX receiving. Therefore, if your TNC 2 does not have a tuning indicator you may find tuning difficult. An add-on tuning indicator. MFJ1273 is available from MFJ Enterprises. Inc. for the TNC 2.

Once entering the Weather FAX mode, the TNC 2 is in standby-receive mode. This means that the TNC2 is listening to the radio for the distinctive "tic-tic" that indicates the synchronization period at the beginning of a picture. If the TNC2 hears the "tic-tic" well enough. it will establish a lock to the signal and start printing to the screen.

The TNC2's built-in LOCK detects the beginning of each picture before starting to print. This insures each picture will be printed from top to bottom. If you want the printer to start to print in the middle of the

MFJ TNC2

MEMORY EXPANSION UPGRADE

picture. you may force a lock on the picture and the printer will begin to print upon the "force lock". To force a lock. you simply type the letter "L" while in the FAX standby-receive mode.

If the FAX picture appears to be printed shifted to the right. you can type the "<" key to shift the picture to the left. Each repetition of the "<" key will shift the picture 1/10" to the left. To shift the picture to the right. use the ">" key. Each repetition of the ">" key will shift the picture to the right l/10". For example, if you needed to shift the picture to the left I inch. you would press the "<" key ten times. The picture can be shifted to the right or left at any time during printing.

If the picture appears to be printing diagonally to the left or to the right, this indicates that the master CPU clock on the TNC 2 may not be in frequency with the transmitting signal. To correct this problem. you will need to remove the

cover of the TNC 2 and adjust the capacitor trimmer,			C47. This adjustment
does not require am special equipment_ Simply adjust			C47	about 1/8 of
a rotation at a	time and let the primer print a few lines of the FAX picture.
If the picture seems to be getting worse. rotate		the trimmer in the opposite
direction. Repeat this procedure until the picture is straight vertically.
Weather FAX	pictures received can also be	saved	to	the disk. This

operation is described in the software documentation of your computer program.

Terminating FAX Printing

Printing of a FAX picture can be terminated at any time during the printing. You must type a CTRL-C twice (CTRL-C. CTRL-C) in order to terminate FAX printing. The TNC 2 will return to command mode, and printing will stop.

NEW COMMANDS FOR 1.2.6

MNonax25ON:OFF

Default: OFF

MNonax25 is defaulted to OFF. When MNonx25 is OFF the display of nonAX.25 packets is inhibited. TNC 2 will display only AX.25 packets. Setting MNonax25 ON will cause TNC 2 to also monitor non-AX.25 packets, for example those associated with TCP/IP and NET/ROM or TheNet links. Display of non-AX.25 packets may not be understandable to the user.

+ 42 hidden pages