Ham Radio 2000 #1

home *** CD-ROM | disk | FTP | other *** search

/ Ham Radio 2000 #1 / Ham Radio 2000.iso / ham2000 / packet / baycom / tfpcx210 / tfpcx.eng < prev next >

Wrap

Text File | 1993-11-20 | 31.3 KB | 777 lines

Translated by Denis Godfrey, G0KIU (mni tnx) There may be a more recent translation, but I haven't got one. 73s Rene, DG0FT ------------------------------------------------------------------ TFPCX v1.10 Resident AX.25-Controller for PC without TNC (Free for Radio Amateurs, No Commercial Usage) Rene Stange, DG0FT (ex Y51GE) INTRODUCTION TFPCX ((T)he (F)irmware (PC) E(x)tended) is compatible with TheFirmware from NORD><LINK and runs resident in the Background as an AX.25-L2-Controller on IBM Compatible PC's (Not on ATARI ST). The output is able to be sent to a simple Modem (e.g. BayCom-Modem von DL8MBT und DG3RBU) and via a Software Interrupt able to communicate with known Terminal Programs such as: SP from DL1MEN and THP from DL1BHO in the WA8DED-Hostmode, which on this account are able to be employed without a TNC. In this description the Operation with SP will be explained. TFPCX is developed from the KISS-Driver which belongs to the distribution of SP and will be employed similarly. The KISS-Interface of the TFPCR has been replaced with HDLC-Send and Receive routines, so that with the TFPCX (still!) will be able to operate with no KISS-TNC's and Controller (e.g. PK232). As Modem-Ports all COM- and LPT-Ports (e.g. for Digicom-Modems) are usable. In short is able to be controlled with only a Modem. The Program is also operable in Terminal-Mode (Stand alone) and contains for that purpose a simple Terminal-Routine. Preface ------- After the most positive reaction to the release of TFPCX v1.01 and the further development of DAMA-Digipeaters I saw myself obliged to bring TFPCX to the 'latest' level and to make compatible to TF 2.3b. Nothing has altered from the basic Function. As a further innovation TFPCX now has a Soft-DCD (Programmable Squelch Barrier) and makes possible an internal self connection for internal Test work. Also for non-DAMA operation this version offers advantages. I must however advise, that I am not able to guarantee, that the TFPCX will function problem free on all PC's. Especially on slow Computers it gives partial Receive- and Send Problems. XT's with operating speeds under 8 MHz are not usable or only within limits. This is not a commercial product, so I accept no responsibilty for its non-operation. In the Majority of cases the TFPCX-User there will be no appearance of problems. Conclusive evidence of its Functioning is only able to given by a Test on the individual PC. Nevertheless TFPCX places negligible demands to the compatibility of the employed Port compared to Baycom, so that it also runs to some extent on Computers which are not BayCom- suitable. With confusion about the operation of TFPCX in connection with SP on [1] reference (read under TFPCR). I start out in this description with the assumption that there is already a functional Modem on hand. Who employs a Baycom Modem, is contained in [2] Advice for the setting to work. I thank all YL's and Om's, who have contibuted and contribute with the advice for the further development of the TFPCX, also if number of their ideas are not yet realised and a Time delay for the reply is important. On this account I offer all, with appearing problems to have a look in this documentation first, then for many questions here is given a certain answer. A special thanks intended for all contributions! Also for myself, I have rejoiced at the positive reactions and support of the Radio Amateurs, that has flowed in for development of TFPCX, respectively who helped to get the TFPCX to this level (Sigi (DL1MEN, NORD><LINK, the BayCom-Team and others.). 73s from Rene, DG0FT @DB0KG Strausberg, 26th. December 1991 Innovations since v1.01 ----------------------- - compatible with TheFirmware 2.3b DAMA from NORD><LINK - Soft-DCD (programmable Squelch Barrier) with switchable Send-/ Receive notice (Option '-NC', Command '@C' for the equalisation) - internal Self Connects possible, all transmitted Frames will also be inspected as received Frames (Self Connect will be urgently recommended) - automatic SSID-selection with Multi-Connects of a Station, if installed SSID already created - 600 instead of 400 free Buffer, TFPCX now occupies 54K in the RAM - Option '-ND' for the delaying of Disk Access during the Send and Receiving (Important with Problems) - Bug remedied, which on 486's made the Unloading impossible - Option '-B9600' no longer exists (also for 486'ser too much) Copyright --------- TFPCX may be passed freely to others for the usage in Amateur Radio. It is not permitted for the Program to be used commercially or to be sold commercially. A guarantee for a correct functioning will not be given. The User has no right of recourse, in the event of a Malfunction of TFPCX. The Program TFPCX has been developed by DG0FT by utilisation of the Source Code of the PD-Programs TFPCR v1.60 from DL1MEN and the PD-Sources of the TheFirmware 2.3b from NORD><LINK (Original version from DC4OX, DAMA from DL8ZAW, modifications from DB2OS, DF2AU, DF7ZE, DK6PX, DL1BHO, DL1MEN, DL4YBG, DL9HCJ and others) Quick Start ----------- For all who prefer to find out for themselves, a BayCom Modem and a normal Ultra Short Wave-Rig with 1200 baud is required. - he who employs an XT, should read further because tests should be made to ensure that the Computer is fast enough. - SP (from 5.02) installed, then whether one uses TFPCR - TFPCR.COM replaced by TFPCX.EXE - BayCom Modem installed on a COM Port - 'TFPCX PCOMn' called (n is the Number of the Port) - Start SP - If there are problems then one should read further - With 'TFPCX -U' :- TFPCX is able to be unloaded. Principle of Operation ---------------------- TFPCX is a TSR Program, that must be called before activating SP and is installed resident in the RAM. If the foregoing is satisfactory, the DOS-Command prompt returns and the next Program will be able to be started. The System behaves as if a TNC was connected, external connects are possible and it stores all incoming Information. As soon as the Terminal Program is started, the received Text will be displayed on the Monitor. The communication with SP follows by way of a Software Interrupt. Here no difference in principle to the employment of TFPCR should be encountered at this point. TFPCX is similar to the Program L2 of the BayCom System by Flori (DL8MBT) and Johannes DG3RBU. Here SP takes over the role of the employed Program SCC. What is truly new in comparison is, that the TFPCX has the ability to control the Modem and is in a position to receive and send AX.25-Frames without a TNC. A different procedure will be employed here, to that in BayCom, which also has advantages as well as disadvantages. The requisite normal timer produces the System Timer (8253 Channel 0), activates the 3,600 times per second Interrupt 8 (For 1200 Baud), which already places a known claim on the Computing performance of the PC. Therefore the TFPCX on normal IBM XT's with 4.77 Mhz operation is not compatible with SP, 8 Mhz should however be sufficient. The greatest problem is that the Interrupts of the timer may not be protracted too long, so that an orderly reception of Packet is possible, and the transmitted Frames will not be mangled. That is able to happen, e.g with Disk-Access. A crude summary of what is able to be awaited is given in the following Table (Without Guarantee). PC XT XT 286 386 MHz 5 8 12 20 Baud 300 * * * * 1200 ? * * * 2400 / ? * * 4800 / / ? * * Operation possible ? Operation possibly with some restrictions / Operation not possible Another problem in this connection are Programs, which themselves make demands on the timer. (e.g. MS-Windows, most Mouse Drivers or MS- Quick 2.51 that I have used.) These Programs are not able to be used as long as TFPCX is active. Contravention will be punished with false System Clock running, extreme retardation of the Computer or System Crash. Up to now it has been comments about disadvantages, nopw what is more positive: what is overlooked is that SP through it's longer development history offers more features than BayCom, the TFPCX does not require a fully compatible COM-Port because the Serial Controller will be employed as a Simple In and Out-Latch. The Port must not be Interrupted and it is able also to employ all LPT Ports as an Interface. (e.g. For Digicom Modems, deliver the 5V level) Also new hope for people, who have had no luck with BayCom ! Modem Connections ----------------- It was not possible for me, to produce a new Modem yet, that is able to be substantially better. So I have retained the Quasi-Standard BayCom Modem, that many YLs and OMs already own. Additionally the possibility remains to connect another Modem (e.g. from Digicom) via a Centronics Port (from me the original variation) Here are the Connections of the Port. COM Port [2] Signal 25 pin 9 pin Operation DTR 20 4 Data Send +/- 10V RTS 4 7 PTT, High active, -12V=RX +12V=TX CTS 5 8 Data Receive GND 7 5 Ground. TXD 2 3 +12V for Baycom-Modem LPT-Port DATA 7 Data Send, TTL Level DATA 9 PTT, High active, 0V=RX, 5V=TX BUSY 11 Data Receive GND 18-25 Earth. The Firmware v2.3b ------------------ Here shortly, something will be said about the realisation of TFPCX v2.3b. The Firmware is able to be employed in two types of operation. (Terminal and Hostmode.) which is also possible by every TNC. The difference to a normal TNC is only that, the Data exchange ensues not by the serial Port but by Software interrupts with different subordinate functions. In the appendix this Software Interface is described. are listed. The Firmware offers a series of Commands, which with the ESC-Key will be initiated and executed with <RETURN>. In the Appendix a short collection of the realisable Commands are to be found. In [3] the Firmware is documented. The Commands 'A', 'E', 'H', 'QRES', 'Z', '@F' and '@M' do not exist. Here follows an explanation for circumspection of individual Commands: Command Remarks C It is no longer important to manually install the different SSID's for the Multi-Connects of a Station (e.g. Digi- access). TFPCX raises this automatically to a maximum of 15 if the one already installed will be employed This Function SP remains concealed of course. Possibly in the Status Line and in other places stands the False SSID. When at the start, the SSID must be self installed. TFPCX is able to handle 10 Connections simultaneously. Internal Connects are possible. F The Frack-Parameter to be given alternatively in Seconds- or 10 ms-Increments. Values smaller than 16 will not be ignored, as with the 'normal' TF 2.3b but in the new Uniformity converted. Thereby the old Config-Files must be unconditionally altered. P Here with DAMA-Operation the non-DAMA value will be indicated but P=255 used. U The Unattended Mode is able to be switched on, when no CTEXT is defined (Standard Installation). The Report 'NO MESSAGE AVAILABLE' no longer given @C With this Command the Soft-DCD will be balanced. (See further extract below) @T4 This Command is on hand only out of Compatibility Grounds, give the T2-Start Value for DAMA-Operation and the correct time, which will be waiting to be verified to a received Frame. It is from the original Firmware and in the meanwhile has been removed again. @U With this will be determined, whether Unproto-Frames will be transmitted with fixed Poll-Bit (Standard) or without. A few words about DAMA: As soon as on a Port a Connection to a DAMA- Master (Digi-Entrance) is encountered, TFPCX will be automatically switched in the DAMA-Slave-Mode and then only sends when it receives a Frame from the Master, then of course all outstanding Frames on all Ports. It is not required for DAMA special Parameters to be installed. thereby alternative operation is possible problem free. With the 'B' Command is is able to establish, whether DAMA is switched on (Value in Brackets larger than 0). The Frames received from the DAMA-Master (and only these, not the others) contain in the Monitor the addition '[DAMA]' With Tests is has been shown, that the DAMA-implementation in the Firmware 2.3b is not yet optimal. It is found for example, that one with Multi-Connect by reason of too short a Frack, will be noticed by TheNetNode-Digi before all others, what was not intended to be so by the DAMA-Designers is. But it is in every case better to operate a non- optimal DAMA-Slave than not at all. Call of TFPCX ------------- TFPCX will be activated by the following Command Lines. TFPCX [ -N ] [ Load options | -T | -U ] All Parameters are optional, will be preceded with '-' and will be separated one from another by a space. Within an option no spaces are permitted. Upper/Lower Case is not significant. In the first place all options shortly will be listed out in the form, as they are also obtainable in the Help Text with "TFPCX -H". Load options are only relevant with the resident load of the TFPCX and valid until the unload. -N No Messages -T Terminal Mode -U Unload Load options: Default -Pport[:xxx] Modem port (address) COM1 -Bnnnn Baud rate 1200 -Ixx TFPCX interrupt FD -F[file] Send file to TFPCX TFPCX.INI -D Debug mode Off -NB No blinking rectangle Off -NC No carrier display Off -ND No disk access if DCD Off [] Issue is optional | alternative Issue n Deczimal Number x Hexadecimal Number After the Start the following Report should appear ┌──────────────────────────────────────┐ │ TFPCX v1.10 (Dec 08 1991) by DG0FT │ │ TF v2.3b DAMA by NORD><LINK │ │ Free for non-commercial usage │ ├──────────────────────────────────────┤ │ COM1, 1200 Baud, Int FD, 10 Channels │ └──────────────────────────────────────┘ and the DOS-Prompt visible. TFPCX is now installed and occupies circa 54 KBytes of the Main RAM. Here is the meaning of the options. -PCOMn (BayCom-) Modem on COMn (Possibilities are COM1 to COM4) -PLPTn Modem on LPTn (Possibilities are LPT1 to LPT4) The base address of the Port will be taken from the BIOS Data range and must be obtained from there. Most BIOS Versions neglect that for COM3 and COM4. In this case the address will be explicitly set in the Form '-Pport[:xxx]' auch explizit gesetzt werden. Example TFPCX -PCOM3:338 With this call a BayCom-Modem will be employed on COM3, whereby the Base Address will be 338H. This Address must be obtained from The Serial Port description. The number of the Port (here cosequentlt the 3) will be ignored if an Address will be given, but must never the less lie between 1 and 4. As Base address is tolerated the range 100H to 3F8H. The IRQ of the Port is of no interest to TFPCX and will not be used. -Bnnnn Baudrate on the Modem (300, 1200, 2400, 4800) Which Baud Rate is possible on a PC, depends on its operating capability (see Table above). If it will not be worked with 1200, it is also not the Normal BayCom-Modem. Operation with 300 Baud the System Clock loses a half minute in an hour. -Ixx Software-Interrupt for Communication with SP (40-FF) Interrupt FD will be employed as standard prcatice. A difference is only important, if this Vector will be used by other Programs. -N Suppress Messages of the Program If the Messages of TFPCX at the Intialisation are not aesthetically sufficiently modest, it is able to suppress them. But Error Reports will still appear. -NB Switch off Status Flash When TFPCX has buffered unread Information or Status Reports and is not in HOST Mode (Also if SP is not running), a square flashes in the top right hand corner of the Screen, that for example draws attention with a new Connect. SP may remove this by means of ESC 'DOS' or ESC '!, because TFPCX in this case remains in Host Mode. It is now able to start SP and react to a Connect. The Flashing is able to be suppressed with this Option, in the case where it distracts. -NC Supress display of the Channel Status Whilst TFPCX is in the Host Mode (also SP runs) an 'R' will ne displayed in the top right hand corner of the Screen, immediately when a PR-Signal is received and an 'S' displayed, when the Station Transmits. The appearance serves for equalisation of the Soft-DCD. With this Option the appearance is able to be switched off. -ND Suppress Disk-Access verzgern, if immediate receive or send will be actioned (Emergency Expedient) In the case where there are Receive problems with Disk-Access (Packets will not be faultlessly decoded) it is able with this option to prevent, that a Disk Access will be carried out, during an adjacent Signal. That leads of course to a somewhat 'unusual' conditions, because the Computer then shows 'hang up' until the QRG is again free. This option should only be used in an emergency. If TFPCX is not in Host Mode all Disk Access will be immediately executed. -D Test Mode (Debug) Causes with each Timer-Interrupt an edge change at the entry of the Loudspeaker. With 1200 Baud a 1800 Hz-Tone will be heard (Baudrate*1.5). The tone should be 'halfway' clean. Crackling originates, if the Interrupt will be delayed. If a single crackling occurs the Computer is overloaded. Here the dividing line is certainly very difficult to draw, a 'certain Ground Noise' must not yet damage the Function. -Ffile File for the Parameter Installation (will not normally be used, if the File Name fails, TFPCX.INI is effective) If required, this File will be read at the Initialisation and in the Terminal-Mode sent to the Firmware, in order to pre-Install the Parameters. That may be of special interest, if the Program is required to be allowed to run in the background without starting SP or for the Operation in the Terminal-Mode. Normally this option is able to be dropped, because SP itself normally undertakes Intialisation. The File will be sought in the immediate Directory, when no full Path name will be issued. The Character '^' will be transformed into an Escape, with which in Terminal-Mode Commands will be commenced. Line feeds will be filtered out, so that 'file' is able to be created with a normal Editor. An example would be: TFPCX.INI: ^F 300 ^I MYCALL ^N 16 ^O 2 ^P 64 ^R 1 ^T 25 ^U 1 Willkommen in ???? - TFPCX v1.10 - SP offline ^W 25 If TFPCX entirely without Parameters, so it will be assumed that 'TFPCX -PCOM1 -B1200 -IFD' has been used. Installation of TFPCX --------------------- (1) SP so installed, that it is able to work with TFPCR (see [1]). Especially, the following lines must be contained in the SP CFG=TNCS:1 CFG=PORT0:5 CFG=CHANS0:10 SP-Versions before 5.02 should not be used, because the TFPCR-Interface does not yet exist in the correct form. Where TFPCX is required to be operated in High RAM, 'CFG=PORT0:5H must be used. This variant requires that no further TNC will be employed by TFPCX. However Multi-TNC Usage by the employment of TFPCX functions. Therefore TFPCX is able to be employed only for one HF-Port and TFPCR is not simultaneously loadable. One must be clear that the Interrupts of the Serial Port are impossible to be made on which TNCs are attached, so that impeccable AX.25-Frames will be received and transmitted. On this account a faster Computer is already required. All that belongs to TFPCR (TFPCR.COM, UNTFPC.EXE, AUTOKISS.CFG) is able to be erased (the original Diskette naturally in safe keeping). Therefore the Data TFPCX.EXE should be copied into the same Directory that SP.EXE resides. (2) Now for the Modem on COM1-4 or LPT1-4 to be connected and TFPCX called. If COM1 is not used, the Port Parameter must be given (see above). If the System hangs for an extremely long time after the load (before the Disk is accessed): is the PC overloaded with the Baud Rate? (3) Next SP will be started. No Report Case. TNC#0 - (TFPCR / FE) in Hostmode displays, has something gone wrong with the SP-Installation or TFPCX has not loaded. Newer SP-Versions are able to distinguish TFPCR and TFPCX and eventually show a somewhat varying Report. Now one looks if there is a QRG on the PR-Operation, and switches on the Monitor with <ESC> 'MISUC'. If in spite of incoming signals no Frames are able to be indicated, quit SP again, remove TFPCX with 'TFPCX -U' from RAM and re- start it again with the Option '-D' added. Now a 1,800 Hz tone should be heard from the Loudspeaker of the PC. (with 1,200 Baud). If all is quiet, the PC has either an incompatible Timer (Then anything further is pointless) or the 'Chirper' simply does n't work. (I have that once already). Now SP will be called again, and accurately pick up one's ears. If a single Crackle Concert sounds, the Computer is not fast enough to react to the Interrupts of the timer (during the loading a Crackle is not detrimental). If the sound is relatively clean, could the error lie with the Modem or the HF-Technique. (4) If the Monitor operates, one is able to attempt a Connect. Thereby the PTT of the Transmitter should be observed. All should now function correctly. It is also conceivable, that reception fails, but mutilated Packets will be sent. Where SP is usually with TNC2 perhaps it will be some other Time constraint. So flash the QRG-Indicator on the Monitor Screen and the alter the Connect Bell. This constraint is is completely normal, would be able to be remedied in SP and is able to be taken will in hand. TFPCX removal from RAM ---------------------- With the Command 'TFPCX -U' TFPCX removes itself from the RAM. It is not necessary to load an extra Program. The Communications-Interrupt will be automatically found and will not require to be declared. Terminal-Mode ------------- With 'TFPCX -T' a simple Terminal-Program will be started, with which one is able to operate without SP. Before this the resident TFPCX is loaded (as described above). One must call the Program twice with different Parameters in order to arrive in the Terminal-Mode. With ALT-X, exit from the Terminal-Program will be achieved. Previously one should switch the Monitor off with <ESC> 'MN', if was active, because otherwise unimportant saving of the Buffer will occur , and problems result with the eventual starting of SP. If it is required to use only the Terminal-Mode (e.g. on slow Computers) it is an advantage to employ the option '-F' for the installation of Standard Parameters. The following Batch File helps for this: TERM.BAT: @ECHO OFF CLS TFPCX -N -F TFPCX -T TFPCX -N -U Soft-DCD -------- TFPCX now has a programmable Noise Barrier (Squelch). It is able to to allow the Squelch of the Receiver to be be fully open and TFPCX decided itself, whether a genuine PR-Signal is being receiver or only noise. The Soft-DCD will be controlled through a new Command '@C', with which one install the chosen threshold. As a Parameter a number from 0 to 63 will be issued. With '@C0' the Soft-DCD is switched off and TFPCX retains as before. This is the Standard Case. With all other Values the Noise Barrier on. At all times the larger the value is, the stronger is the Soft-DCD recorded. For the facility of the adjustment an 'R' will be indicated in the top right hand corner of the Screen when a signal is recognised, and an 'S' when the Station sends itself (only when SP is running). With too small a value the DCD Indicator flickers, with too large Values Signals will be no longer correct and too slowly recognised. For the best raise the Parameter so far and listen to QRG, up to the true notification. With that an eventual compromise will be found. A good Value is '@C25'. IMPORTANT The Soft-DCD should only be employed if one does not have a Hardware- Squelch that is in good order, because the recognition is eventually not problem free. The conditions with other Baud Rates than 1200 have not been tested. For the best probe and decide yourself ! Error Correction ---------------- In case there are problems with bad reception or ones own outputs are not able to be decoded by other Stations lies the eventuallity thereon, that the Timer-Interrupt Routine for TFPCX's 'life importance' will not always be called up correctly timed, because the Interrupt was barred to long. This problem stands before everything with Disk Access, Access to the Extended Memory (e.g. RAM-Disk), Toggled in the Protected Mode (e.g. EMM386) and slow Keyboard Drivers. In the last case, the Driver CKEYGR.COM from the SP-Diskette helps. Also many TSR Programs bring problems. One is only able to attempt, to dispense with all of these Problem sources, but what is not always possible. In case of emergency the option '-ND' also helps, if Disk Accesses are to blame. With the BayCom-Modem there are possibile Problems through the stabilised Voltage supply with the BayCom Modem. in connection with TFPCX. Here the TXD-Control remains static on approximately +12V whilst Baycom delivers a time signal on this condutor. For this reason the supply voltage of the Modem lies somewhat higher and the potentiometer Pin 7 of the TCM3105 delivers a Voltage differing from the ideal value. In this case a new balance of the potentiometer is necessary. (see [2]). * * * Anyone who has an interest for the Program, send an empty Diskette and a self address and an adequately stamped envelope to: Rene Stange O.-Grotewohl-Ring 34 15344 Strausberg Germany Possible Diskette-Formats: 3 1/2" 720K oder 1,44M 5 1/4" 360K oder 1,2M Please particularly observe the foregoing Text! I make no financial gain, it is not possible for me to pay the postage out of my own pocket or more expense to supply a Diskette for copying, to place in the completed envelope and take it to the post. APPENDIX Functions of the TFPCX-Interrupt -------------------------------- There exists four lower functions, which by the Value in the Register AH is able to be selected by a call. Posible Parameters will be delivered into AL. AX contains by return, the result or FFFF if a non- existent Function has been selected. All presented Characters should be read, before the next input should be made. AH = 1 Request, whether a request Character present Returns AX = 0 No Character present AX = 1 Character present AH = 2 Character request, only calls if Function 1 has imparted, that a Character is present. Returns AL Character code AH = 3 Output of a Character to the Firmware Parameter: AL Character to be output AH = FE Request for the TFPCX-Version Number Returns AH = 1 Main Version Number AL = 0AH Sub-Version Number Three Bytes after the jump into the TFPCX-Interrupt-Routine stands the Identification 'N5NX', which operation Interrupt on hand the Terminal Program is able to self ascertain. Commands of TFPCX ----------------- COMMAND PARAMETER DESCRIPTION B(120) 1...600 DAMA-Timeout-Time (Seconds) 0 DAMA-Switch-on Blocked C C/Sign1 [C/Sign2...C/Sign9] Connect-Path (in Channel 0: unproto) D Sever connection F (300) 16...65535 Start Value for SRTT (10ms) 1..15 Start Value for T1 (Seconds) G [0] Get Info in the Host-Mode [1] Get Status in the Host-Mode I Call Sign Own Call Sign JHOST (0) 0 Terminal-Mode Switch on 1 Host-Mode Switch on L (0...10) Status report for the Channel M (N) NIUSC+- Monitor Operation N (10) 0...127 No. of requests (0=infinite) O (2) 1...7 No of unacked Packets P (64) 0...255 p-Persistance Value R (0) 0 Digipeat Off 1 Digipeat ON S (0) 0...10 Channel Number (0 = Unproto) T (30) 0...127 Wait Time (DW) for PTT 10 ms. U (0) [Text] Connect Text suppressed [Text] Connect Text ON V (2) 1 Protocol Version 1 2 Protocol Version 2 W (10) 0...127 Timeslot for p-persistance 10 ms. X (1) 0 PTT for TX Suppressed 1 PTT for TX Free Y (10) 0...10 Maximum quantity of Connections @A1 (7) 0...65535 SRTT-Smoothing, if RTT rises (SRTT'=(A1*SRTT+RTT)/(A1+1)) @A2 (15) 0...65535 SRTT-Smoithing, if RTT falls (SRTT'=(A2*SRTT+RTT)/(A2+1)) @A3 (2) 2...16 Factor for T1 (T1=A3*SRTT) @B 0 Shows quantity of Free Buffers @C 0 Software-DCD OFF 1...63 Threshold for Software-DCD @D (0) 0 Full Duplex OFF 1 Full Duplex ON @I (60) 0 IPOLL OFF 1...256 max. length of IPOLL Frame @S Immediate Link Status @T2 (150) 0...65535 Timer T2 (10ms) @T3 (18000) 0...65535 Timer T3 (10ms) @T4 (10) 0...65535 Timer T2 with DAMA (10ms) @U (1) 0 Unproto-Frames without Poll 1 Unproto-Frames with Poll @V 0 Call Sign Check OFF 1 Call Sign Check ON [] Optional Parameters () Standard installation Bibliography ------------ [1] DL1MEN: Manual of Eskay Packet (SP) from v5.02 [2] NORD><LINK: Documentation for the Firmware 2.3b [3] DL8MBT, DG3RBU: BayCom - Documentation for the Modem