Oakland CPM Archive

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

/ Oakland CPM Archive / oakcpm.iso / sigm / vol158 / yamimpl.lqt / YAMIMPL.LST

Wrap

File List | 1985-02-10 | 42.8 KB | 990 lines

Implementation Manual for YAM (Yet Another Modem) by Chuck Forsberg Distributed with YAMC86 (Converted for CI C86 and CP/M-86) by Paul Homchick Yam Implementation Manual Revised 9-10-83 Page 1 1 FILE TRANSFER PROTOCOL 1. FILE TRANSFER PROTOCOL The transmission of pathnames in batch mode differs from that used in MODEM7. Yam sends the pathname as a null terminated string in a standard Ward Christensen type packet with a sector number of 0. The sender may append the following additional information starting one byte after the null that terminates the pathname: sprintf(p, "%lu %lo %o", f.st_size, f.st_mtime, f.st_mode); where st_size is the exact length of the file in bytes, st_mtime is the modification date in seconds since 1970, and st_mode is the file mode, as defined for Unix V7/Sys3. If the mod time is unavailable, a 0 value will cause the receiver to ignore it. If the file mode is unavailable, a 0 value will cause the receiver to ignore it and use a dafault file mode. Disk specifiers (B:) are not sent. Directory names of full pathnames are not (generally) sent. If this information (including the trailing null provided by sprintf) exceeds the 128 byte standard sector length, a long sector must be sent. The sender waits for an initial NAK before sending the pathname. An explicit NAK is sent by the receiver at intervals when is ready to receive a pathname. Upon receiving and acknowledging the pathname packet, the receiver opens the file and then sends the initial NAK for the data in the file. A null pathname terminates batch transmission. The remainder of the pathname sector is set to nulls. 2 Installing Yam 2. Installing Yam Yam consists of yam.h, yamsys.h, yam8.asm, and yam[1235710].c. Yam currently supports the Z89 (with aux board), Cromemco TUART, TRS-80 II, and Apple (currently with Z19 console). Yamsys.h is not part of the distribution; one of the configuration dependent header files is copied to yamsys.h. SOME of these files are: Yamz89.h is used for Z89 computers (check the port definitions to be sure they agree with your usage.) Yamtuart.h is setup for a TUART board at 60H. Yamz89xm.h describes an XMODEM configuration with the Z89. Yamtrsii.h describes a TRS-80 Mod II. One of these (Or one YAM/XYAM Version 4.24 Page 1 Yam Implementation Manual Revised 9-10-83 Page 2 you write for your system) should be copied to yamsys.h before compiling the files. YAM also references some of the definitions in BDSCIO.H. When cross-compiling a version of yam for a different system, be sure to reference a bdscio.h file suitable for the target system. Alternatively, one might #undef CDATA and any other definitions which otherwise would speak with forked tongue; YAMLYLE.Hwill be an example of this trick. Starting with Version 3.08 there will be multiple versions of yam5.c depending on the target system. There have been few changes to yam5.c (except for porting to new systems), so you should be fairly safe hanging on to your current version. If you do have a special version of yam5, please edit out ALL code and comments not directly relevant to your application (including the unused versions of readline) to minimize storage space and transmission time for RCP/M's archiving yam. Compilation should be with -e ???? for all files and -o for yam[235] and yam10 for best runtime performance. Note that yam[147] are NOT compiles with -o; the execution speed of the functions in these files is unimportant, and it is better to save code space by not using -o. Consult the .sub files for examples. If the externals start below the end of code, YAM will say "urk" and exit, hopefully before doing anything REALLY nasty. Yam should be linked with the object module with the largest set of "local globals" first. Currently, this is in yam10. These variables overlay similar variables in some other files. They are not required simultaneously, but the linker must see the largest common area first to allocate sufficient room for them. (N.B.: I do not recommend this hack as a general method!) Care should be taken to ensure that all .crl files are compiled or assembled with compatible versions of cc1 and bds.lib. Yam can be made somewhat smaller if the -o is left out and the external address is downsized accordingly. To make the smallest YAM possible, define CDOS and RESTRICTED and then leave off as many optional #defines as possible. The bdsnew library (assembly language versions of some standard functions) may be used with slight improvments in code size and speed. (Bdsnew library is named bn.crl in the .SUB files used for yam.) YAM is handy for transferring files between directly connected machines; hence all the attention to high speed operation. If your machine uses a different type of UART chip, or a built-in modem card, then the yamsys.h and yam5.c files will need work. YAM/XYAM Version 4.24 Page 2 Yam Implementation Manual Revised 9-10-83 Page 3 Compilation and proper operation of YAM cannot be guaranteed with BDS C versions prior to 1.50a. If you don't have that version, send 8 (maybe more now!) bucks and a copy of your software license (a Xerox of your distribution disk showing its label should do) to: BDS C Users Group Robert Ward Dedicated Microsystems Inc 409 E Kansas ST Yates Center, Kansas 66783 Versions before 1.46 are a no-no. 3 PROPAGATING YAM 3. PROPAGATING YAM Often the question arises, "How do I get YAM (or whatever) into this neat new machine with the *%!@$@ format disks? 3 1 Binary Serial File Transfer 3.1 Binary Serial File Transfer The b mode was put in just for you! First, cross-compile a version of YAM with a yamsys.h file appropriate for the target machine. Then, connect the two machines RS232 ports together, and initialize those ports so they talk to each other. Presumably, YAM is running on the host machine. Now run ddt, sid, zsid, dcon, or whatever and write a tiny program up in fairly high memory (above the highest address used by YAM, say 7000h). This program will: Set HL to 100h Set HL to 100h Wait for UART for data available Wait for UART for data available Input data from UART Note UART must be in 8 bit no Input data from UART (Note: UART must be in 8 bit, no parity mode parity mode) Store data to memory mov m a Store data to memory (mov m,a) Increment HL Increment HL Jump to 2 above Jump to 2 above. When the file is all sent, interrupt the program, jump to location 0. Then you can save YAM.COM. If you can't interrupt this program without blowing it away, you'll have to change it to detect the end of data (perhaps count the number of bytes received in the DE register) and make the program jump to location 0. 3 2 Hex File Transfer 3.2 Hex File Transfer Another possibility would be to unload the yam-target.com image into a hex file ( UNLOAD2.ASM works fine ). Then run YAM/XYAM Version 4.24 Page 3 Yam Implementation Manual Revised 9-10-83 Page 4 pip in the target machine with input from the serial port and output to a file using pip's B parameter. With the B parameter, pip buffers incoming data in memory until an XOFF (Control-S) is received. To get that, send the file from the host with "yam f file.hex" and from time to time hit two ^S's on the host keyboard. The first ^S stops the transfer, the second will be passed to the other machine where pip will see it. When pip has written out the buffer, type ^Q on the host to resume. (Be sure to stop often enough so pip's buffer doesn't overflow.) (With pip, go slow -300 baud is much better then typing it in by hand!) Finally, load the file with the target system's load command. Also, if the target system is echoing characters (TTY: input device) the FE file command may be easier to use. If the target system echos characters, use the ``fe filename'' command which waits for an answering echo before sending the next character. If that doesn't work properly, try ``ft'', slowing down the transfer with the t mode. Once you have a working yam running on target machine, other files come across effortlessly with the batch file transfer option. Happy propagation and may your machines trap fertile YAM's. 4 Important define s 4. Important #define's MODOUT c MODOUT(c) This outputs the character c to the modem. This macro need not check whether the modem is ready for a character as that has already been done. MODOUT(c) must return immeadiately regardless of what is in c. LPOUT c LPOUT(c) Likewise, unadorned output of c to the printer. LPOUT(c) must return immeadiately regardless of what is in c. POREADY POREADY This define returns non zero if the line printer is ready to accept a character. It must always return 0 if LPOUT(c) would not return immeadiately. If POREADY is slow, enabling the printer at high baud rates may cause characters to be lost. TTYOUT c TTYOUT(c) Unadorned output of c to the local display. YAM checks that the local display is ready before executing TTYOUT(c). TTYOUT(c) must return immeadiately regardless of what is in c. Caution: don't use bdos function 6 which has special cases for 0xFE and 0xFF. YAM/XYAM Version 4.24 Page 4 Yam Implementation Manual Revised 9-10-83 Page 5 CICHAR CICHAR Unadorned unconditional console input. This must not trap on any control characters needed for host communications. MYSYSTEM MYSYSTEM Defining this causes yam2 to be compiled with a call to yam4.c for handling the Compuserve A protocol for file transfer (see 2 mode). Unless you know what you are doing, you should use the following even if it is a bloody lie as xftran may not accept something original. If this is included, you will need yam4.c, otherwise not. #define MYSYSTEM "#CPMHeath/Zenith,CC,HC,PA,PL\015" KBDBRK KBDBRK This defines the keyboard character that translates to a break in yam3. It should not be a normally used character. FNXEXT FNXEXT This character unconditionally exits term function. Normally, this is defined only if a special function key is available as that code cannot be transmitted. If FNXEXT is defined, FNXREP (replot) must also be defined. ANSWERBACK ANSWERBACK This string is transmitted from term function in Q mode in response to keyboard ^F or ^E received from remote. Conventionally, ANSWERBACK consists of "\\r\\n<phone-number> <user name> <city>\\r\\n\\021" where city is a three or four letter abbreviation specified by Western Union Telegraph company. Teletype answerbacks are limited to 20 characters, a limitation which needn't concern us. PHONES PHONES This file (usually "A:YAMPHONE.T") contains a list of names, phone numbers, and baudrates. The names must be in lower case. HELPFILE HELPFILE Contains a short summary of commands and other useful information about YAM suitable for use as an online cribsheet. Currently a helpfile exists only for XYAM. CDOS CDOS Makes YAM work on CDOS operating system by deleting CP/M 2.2 operations such as user number, calculate file length, etc. If you have CP/M 1.4, CDOS just might do the trick for you. Since my Cromenco system has refused to work for the batter part of a year now, there is an excellent chance yam won't compile with CDOS defined. In addition, newer versions of BDS C require the CP/M 2 features, and yam won't compile YAM/XYAM Version 4.24 Page 5 Yam Implementation Manual Revised 9-10-83 Page 6 with earlier versions. So there. KBMASK KBMASK This is normally 0177 to strip parity from keyboarded characters, but may be 0377 if a full 8 bit keyboard is used. USERINIT USERINIT Causes init() to call a user supplied function userinit(). This may be used to set up interrupt vectors, global variables, etc. Note that userinit is called in response to the init command. USEREXIT USEREXIT Defining this causes a call to userexit() before any normal exit() call. If userinit() has ``stolen'' something from the operating system, (such as an interrupt vector) userexit should ``return'' it. Since yam is often exited with control C, that should be trapped also. TERMREPLOT TERMREPLOT A string enclosed in quotes which clears the screen and sets the terminal to the mode desireable for replot. Replot assumes that TERMREPLOT turns off line wraparound. TERMRESET TERMRESET A string enclosed in quotes which sets the terminal to the mode desireable for the term function and clears the status line (if any). This string should not clear the screen. It should set the terminal in the mode(s) expected by vi or other host based screen editors with which YAM is to be used. In particular, special effects (if any) of TERMREPLOT should be negated. TERMINIT TERMINIT This string should unconditionally initialize and clear the screen. CLEARS CLEARS String to clear the screen and home cursor without changing modes. CLEARL CLEARL String to return cursor to left margin and clear the current line. If the "clear line" command does not return the cursor, a carriage return must be included in this string. INTOREV INTOREV String to turn on reverse video. OUTAREV OUTAREV String to turn off reverse video. YAM/XYAM Version 4.24 Page 6 Yam Implementation Manual Revised 9-10-83 Page 7 RXNONO RXNONO Define this as a string of characters, any of which would cause your terminal and/or cbios grief if not suppressed by term function. STATLINE STATLINE Define this if your terminal has an extra (viz., 25th) line usable for status information which does not scroll up nor interfere with scrolling. lpstat() writes to the entire status line, clearing out any previous contents. pstat() writes starting at the 48th position, not disturbing any information written by lpstat(). T4014 T4014 Special code for storage tube terminals. NOSCROLL NOSCROLL Special considerations for terminals which do not scroll, such as storage tube terminals. MODEMSTUFF MODEMSTUFF If you provide routines setbaud(), readbaud(), bye(), and onhook(), define MODEMSTUFF to exclude the default dummy routines. AUTODIAL AUTODIAL If your modem supports autodial, write your own version of dial() and define AUTODIAL to suppress the default routine. FLIP FLIP If you have a flip() subroutine in your yam5, this causes flip to be included as a command. See yam5pmmi.c for an example of a flip routine. MIERROR MIERROR If your uart has a separate register for error bits (not the register that holds receive data available), mierror should be an expression which returns non zero in case of overrun, framing, or other error, but not carrier dropout. This version of readline has not been tested. MIREADYERROR MIREADYERROR Define this if data available and the error bits are in the same register, especially if reading that register clears some error bits, or if the error bits are valid only if data available. IOTYPE IOTYPE This defaults to char for i/o mapped systems with 256 ports. This may be defined to unsigned or long for systems with more ports (8086 or memory mapped i/o). Z19 Z19 Generates output for Z19 functions, especially status (25th) line. YAM/XYAM Version 4.24 Page 7 Yam Implementation Manual Revised 9-10-83 Page 8 USQ USQ Allows the type command to automatically recognize squeezed files and display them in ASCII form. Adds 1000 hex to program size. RXLOG RXLOG Log all files received from remote systems in RXLOG. Information stored includes user number, disk, filename, baudrate, and the name of the remote system given in the last call command (LASTCALR in xyam). TXLOG TXLOG Log all files transmitted to remote systems in TXLOG. Information same as above. LOGFILE LOGFILE Must be defined if either of the above are. NATHAN NATHAN Students of American History will recall the famous patriot Nathan Hale who said "I regret that I have but one asterisk for my country." Octal code 052. 5 Tuning Parameters 5. Tuning Parameters Yam uses a number of tuneable parameters for portability. The values used depend strongly on the speed of functions and operating system calls used to interrogate the keyboard and modem port. They are also affected by the clock speed and code quality of the compilier used. These parameters have been added on a somewhat ad hoc basis, so one should grep the source files to determine the extent of their effects. CLKMHZ CLKMHZ This is a ``master'' parameter. Use it to calibrate the timeout in readline (see yam5 or equivalent). MOMCAL MOMCAL Should give a delay (see yam3) as short as possible while still allowing the user to comfortably double-stroke control-E or control-V. SCREAMER n SCREAMER n Compiles a call to yterm() instead of term() if baudrate > n and no special modes have been set which would be rendered useless. Without yterm, maximum baudrate may be limited to much less than 9600. Yterm is written in assmebly language and must be modified slightly according to the local hardware configuration. The yterm function is in yam9.csm. YAM/XYAM Version 4.24 Page 8 Yam Implementation Manual Revised 9-10-83 Page 9 Note: if you miss only the first few characters in a line, and if your system has memory mapped video, screamer won't help you much; you need to speed up the scrolling process! Note that yterm lacks much of term's functionality. On a Z89 with direct bios keyboard input, yterm functions at 19200 baud (assuming 19kb crt port!). KBDNOW ! KBDNOW This forces term function to interrogate the keyboard each time a character is displayed to the console rather than when there are no modem characters waiting to be displayed. With computers with interrupt-buffered modem ports, this #define will allow the keyboard to always get a word in edgewise. It is not recommended otherwise. ESCCAL ESCCAL Many terminals send escape sequences for certain keys. In some configurations, these sequences will fail to transmit properly because the modem (300 or 1200 baud) cannot transmit the characters as fast as the terminal generates them. I ESCCAL is defined, yam will check for rapid escape sequences and buffer the following characters. ESCCAL should be set to the lowest number (shortest delay) that will recognize the sequences. This logic is not needed if the keyboard is interrupt driven. This feature may not work if the remote is sending data at maximum speed the instant the function key is used. For more information, study the functions on yam3.c that reference abptr and/or abend. LOWWATER LOWWATER When receiving text from the host in term function, term transmits XOFF (DC3) when the free buffer space gets down to LOWATER, unless Jovemode is set. LINKPORT LINKPORT Causes compilation of code to implement the ``link'' command. See ``ymlink.h'' for typical link parameters. LHPORT LHPORT Local Host port to use for local host during link command. LIDPORT LIDPORT Modem data port for link command. LISPORT LISPORT Modem status port for link command. LIREADY LIREADY Defines a function which tests for a character available from modem when in link command. LCDO LCDO Test for carrier drop-out in link command. LICHAR LICHAR Returns next character from modem when in link YAM/XYAM Version 4.24 Page 9 Yam Implementation Manual Revised 9-10-83 Page 10 command. LOREADY LOREADY Test for link modem ready to accept another character. LOUT x LOUT(x) Macro outputs a character to modem port during link command. LIBREAK LIBREAK Test for break from modem when in link command. CLRLIBREAK CLRLIBREAK Function to clear LIBREAK indication. 6 XYAM Differences 6. XYAM Differences XYAM is produced by defining XMODEM in the file 'yamsys.h'. Consult 'yamz89xm.h' and 'yamx.sub' for an example. Certain #defines are especially applicable to XYAM: RESTRICTED RESTRICTED Certain commands and options are disabled. Filenames with '.BAD' extensions and files with $SYS or TAG2 bits set cannot be opened. They will not appear with DIR or DIRR commands. A file with extension of '.COM' will be uploaded with a '.OBJ' extension. Existing files cannot be overwritten. If a file is received (r command) in error, it will be unlinked. CDO CDO Define a test for carrier drop out so that XYAM will automatically exit T(erm) function when the connection is broken. BYEPROG BYEPROG Bye, O and OFF commands chain to BYEPROG.COM if BYEPROG is defined (as a string). For systems wishing to use a BYE.COM to request comments. 7 Recent Revisions Enhancements to YAM 7. Recent Revisions/Enhancements to YAM 4.26x Converted to CI C86 syntax for CP/M 86 12-19-83 (Paul Homchick). 4.26 4.25 4.24 Added chek command to Lattice and CC86 16 bit versions 8-25-83. 4.22 Minor changes to Jovemode 7-21-83. 4.21 Added Jovemode 7-18-83. 4.20 Changed uses of certain macros to function calls to conserve memory. YAM/XYAM Version 4.24 Page 10 Yam Implementation Manual Revised 9-10-83 Page 11 4.13 Changed crck command printout format. Function init() now calls chngport rather than setting port values directly. Hp125 version checks for proper port number. 6-25-83 4.12 6-12-83 yam1.c default term file xmit mode name (as printed in ``s'' command) changed from ``IMAGE'' (misleading) to ``normal''. 4.11 6-9-83 chngport() in yam5.c return value now checked for ERROR. (Seiko version checks for valid port number.) Bug in CPM-86 getfree() corrected. 4.08 5-30-83 Changes in yam7.c: BDS C 1.50a broke fopenaa code. Fopenaa code removed and refrences changed to fappend in BDS lib. 4.08 Changed replot so screen is cleared whenever buffer pointer is backed up. ESC characters are counted in replot line counting. 4.06 Corrected yam3 and user manual re operation of w and p modes. The off command now dumps and closes any open files. The m command closes any send file before changing ports. 4.04 Fixed yam3 so Ctlview would indicate paritied characters. Added 7-bit mode to enable file transfers with Regulus and/or other brain damaged operating systems. This latest frob requires changes to readline() and sendline() to work; see yam5.c (8 bit version). Removed archive bit (Nof3) stuff to conserve space on 8 bit versions. Fixed view option problem with 16 bit yam2.c. Batch send now skips over files that can't be opened, except for the first. 4.03 Fixed yam3 so CPMEOF is not sent in normal mode. 4.02 Added dump, sum, and wc commands to 16 bit versions. 4.01 Added extended file information to 16 bit versions. 3.53 Some changes in yam3.c for better replot displays with terminals lacking STATLINE. 3.52 Added br (break) command and KBDBRK. Yterm() now updates Lskcnt so the replot will pgae back the same way whether yterm is in use. This was accomplished by a change in the calling sequence for yterm. 3.51 Added userexit code. 3.50 Added replot buffer search commands. 3.47 KBDNOW define added to force keyboard interrogation after displaying data (yam3). Should only be used if input from modem is buffered or if high baud rates are not needed. 3.46 Clear status line after type/list command. 3.45 Removed spurious dumprxbuff in yam1 that caused loss of data if capture file was opened with partially full buffer. Also clear status line after s and r commands if file transfers successful. VERSION now lives in yam1. 3.44 Name changes and typo corrections for portability. 3.43 Nlmode and crmode now affect file xmsn with the sendecho function as well as term. 3.42 inp() and outp() calls in yam3.c changed to equivalent macros for portability. Disk block calculation fixed re Paul Homchick. 3.41 Keyboard excape sequences buffered (see ESCCAL). LOOPBACKNONO and u command removed. 3.39 Modem port selection has been moved from yam1 to yam5. CISlen is no longer a settable parameter. Low is no longer a settable parameter. All parameter commands now take a decimal number; this avoids problems encountered in previous versions when attempting to set GOchar to colon. FE sends YAM/XYAM Version 4.24 Page 11 Yam Implementation Manual Revised 9-10-83 Page 12 an ascii file to computers with character echo (pip file=tty:). A bug which caused spurious XOFF to be sent when sending file in term mode has been fixed. Z100 version. 9-16-82 3.37 Increased some timeouts in yam2.c for better operations with sluggish remotes. 9-1-82 3.35 NULL sends break in yam3 (was ^B^B). 8-28-82 3.34 Changed starting point of replot command and also speeded it up by using externs. 8-1-82 3.33 Changed yterm() to assembly subroutine, p/o yam9.csm. Changed yam8 to .csm format also. Removed y command (selection is automatic). 7-31-82 3.31 Added A prefix, LINKPORT, and completed Micro-Com autodial routine. 7-23-82 3.30 Added k flag for 1024 byte block FTP, as well as other improvements to yam2.c 7-11-82 Added y command, a faster subset of the t command. Capture to file now ignores CR, trnaslates LF into CR-LF unless image mode. Moved time-sensitive functions from yam7 to yam10, allowing memory savings by not using -o on yam7.c. 3.29 Removed Join mode. Added x command. "Added" TTYOUT, MODOUT, and LPOUT macros (with argument) to reduce conditionals in YAM3.C and YAM7.C 6-26 3.28 Added FLIP for PMMI type modems. The memory usage change made in 3.26 has been cleaned up by use of a union to assure correct memory layout regardless of the compiler used. A yam5pmmi.c file for the pmmi modem now exists. 6-12-82 3.27 Changed autodial() function for CAFPERS. 6-11-82 3.26 Further changes to aid maintenance of different versions of yam. Needs BDS C 1.46 to compile due to nested conditionals. init() moved to yam7.c. Memory usage changed allowing larger buffer area. 3.25 NATHAN defined. CIS protocol entry changed to help error recovery. 5-31-82 3.24 Corrected usage of CLKMHZ 3.23 Official 8-bit version. Added -, o mode (Onetrip), and Cislen parameter. Jeff Martin's corrections added to manual. 3.22 Unofficial Version. Includes CIS/MNET A file transfer protocol optional with yam4.c (see MYSYSTEM). Changed Cis02 handling. Changed statline in yam2 to display number of characters received in kilobytes. Some coding changes reflecting awkward sequences discovered while porting to CP/M-86 on IBM PC version. 3.20 New Base Version (for dif's). Changed error printouts in yam2. Documentation update. 3.19 J mode joins short lines when at less than column 40. 3.18 N mode now prepends \\r to \\n when the term function is receiving a file. 1-1-82. 3.17 Added E parameter 12-19-81. 3.16 Setting Squelch (TS ES FS or DS) automatically sets Dumping to not Squelch. In Twxmode half duplex, transmitted file is copied to receive file (if open), and is printed if print mode is on. 12-16-81. 3.15 Added term Q mode for TWX operations with ANSWERBACK. Changed wcgetsec() logic so noise hits on the line before the first sector do not cause a speedup in the timeout parameter. 12-14-81. YAM/XYAM Version 4.24 Page 12 Yam Implementation Manual Revised 9-10-83 Page 13 3.14 Added append option for receiving files, replot K subcommand, changed previous K subcommand to Z. In N mode, keyboard CR is transmitted as NL. 12-11-81. 3.13 For non STATLINE, changed "Awaiting Pathname NAK" to "+" and "Awaiting initial NAK" "^". 3.12 Added replot X and K subcommands, changed type unsqueeze to avoid array overflow problems on long pathnames. Added term function break subcommand (requires sendbrk() function in yam5.c). 11-5-81. 3.11 Added Cis02 mode for Compuserve access, fixed logfile problem (first few files didn't show). Tab expansion fix courtesy Jeff Martin (I thought it was the Z89!) 11-28-81. 3.10 Changed yam10.c to stop printout on ^Z in file 11-22-81. 3.09 Cosmetic change to type command in xyam. 11-17-81. 3.08 Added USERINIT option useful for some implementations. 11-14-81. 3.07 Minor change to yam1.c for benefit of memory-mapped systems 11-11-81. 3.06 IOTYPE added for memory mapped systems List command now distinct from type. Cosmetic changes to opentx(). 11-8-81. 3.05 Added automatic recognition and display of squeezed files. Inclusion of the unsqueeze feature (#define USQ) may require clink -r 800 11-7-81. 3.04 Added GOchar parameter, enhanced view mode 11-6-81. 3.03 Number of sectors and xmsn time printed when opening files 11-5-81. 3.02 Xyam resets user number when exec'ing BYEPROG. 11-01-81. 3.01 Added INITBAUD. Your yam?????.h may need revision. 10-31-81. 3.00 Nomenclature changed to facilitate differential file updates 10-25-81. 2.34 Added era and NATHAN commands, O mode. 10-24-81. 2.33 Changed Unixish "FILE" to struct _buf in yam.h. 10-21-81. 2.32 Added BYEPROG define, deleted T, U, and W commands from XYAM. 10-18-81. 2.31 Corrected tab expansion and kbd XON XOFF handling in yam3.c 10-17-81. 2.30 Supports CRC error checking option compatible with XMODEM45 10-15-81. Chat function now in both yam/xyam. 2.24 Added free disk space report on a: etc. command, Upchuck function. 2.23 Added "crck" command. YAM/XYAM Version 4.24 Page 13