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- A Personal Note
- ===============
-
- Somehow, I've managed to get by for the last 14 years using just ZCPR.
- But like some of you, I have fiddled with the standard ZCPR and
- modified it to suit my tastes. As I added new commands or enriched old
- ones, I've always remained compatible with existing programs, all the
- BDOS replacements, and, most important of all, stayed within the 800H
- space allocation of the original Digital Research CCP. Here are the
- fruits of my labors, I hope you enjoy this CCP replacement as much as I
- do.
-
- Don Kirkpatrick
- 17595 S.W. Pheasant Lane
- Beaverton, Oregon 97006
- <Donald.C.Kirkpatrick@tek.com>
-
-
- Introduction
- ============
-
- This console replacement is designed to run under CP/M 2.2 or any of
- the 2.2 BDOS replacements. It requires a Z80 or better. If you are
- running DRI's CCP or older versions of ZCPR1, this program is a
- significant improvement. If you are running ZCPR3, CP/M 3.0, CP/M
- Plus, or MP/M, this will probably be a disappointment.
-
- If you are familiar with ZCPR3, you will recognize many of the
- enhancements here: comments on a command line, search path for the .com
- file, drive/user change with simple du:, CLEVEL3 command processing,
- proper SUBMIT file facility, and so on. Nothing has been removed from
- DRI's CCP, only new features added. AND IT ALL STILL FITS IN THE
- ORIGINAL 800H, THE SAME SPACE AS THE DIGITAL RESEARCH FIVE COMMAND
- CCP.
-
- Many of the standard commands have been enhanced. For example, TYPE
- and LIST now have options to turn on or off page breaks. Moreover, the
- console check for abort has been improved.
-
- Two commands have been added for use in submit files - SAK and BELL.
- These commands allow you to pause or ring the bell during submit file
- execution.
-
- Before you install this version of ZCPR onto your boot disks, try it by
- running it as a .com file. Just edit the few customizing options and
- assemble the source. After you decide it really is better, load it
- onto your boot track and make it your standard. Complete instructions
- are located at the end of this document.
-
- The complete built-in command list is:
-
- DIR - directory command enhanced to list optionally all user areas
- REN - standard rename command
- USER- move to new user number area on same drive
- SAVE- save specified number of TPA pages or records in a file
- TYPE- display a file on the console with optional page break pauses
- LIST- print command plus optional form feed insertion
- PAGE- send form feed to list device
- ERA - standard file erase command
- ERAQ- file erase with confirmation query at each file
- DFU - set default user number for .com search path
- BELL- send a bell character to the console
- SAK - pause until a key is struck on the console (Strike Any Key)
- SCL - toggle multiple commands per line (Single Command on a Line)
- GET - load a file into the TPA at any specified location
- JUMP- process command tail and execute program at specified address
- GO - process command tail and execute program loaded at 100H
- PEEK- display hexadecimal byte string starting with specified address
- POKE- load hexadecimal byte string starting with specified address
- BOOT- execute BIOS cold boot routine
-
-
- Filename Processing
- ===================
-
- The standard ZCPR3 du: drive/user file specification has been
- implemented. Any filename can be in the du:fn.ft form. For example:
-
- A>era c4:junk*.*
-
- erases files on the C drive, user area 4 without leaving drive A user
- 0. When a user number is found in a filename, that user number is
- placed in S1 of the default FCB. Bit 7 of S1 is set to inform the
- program using the FCB a user number was found.
-
- The * in an ambiguous file name has been improved. Now a trailing *
- causes the remainder of the ambiguous name to be filled with '?', not
- just the fn field. For example:
-
- A>era c4:junk*
-
- is the same as the example above. Previously, junk* was defined as
- 'junk????. '. If you need the ft field blank, type 'junk*.'. The
- question mark still works as a single character wild card.
-
-
- Command Line Processing
- =======================
-
- The current user number is included as part of the command prompt for
- all non-zero user numbers. The prompt is of the form du>, for example
- A2> or B10>. If the SUPRES equate is true, the user number is
- suppressed for user 0 only.
-
- Multiple commands are typed on a single line separated by a command
- separator character. Occasionally, you need to type the separator
- character in a command tail. The SCL command toggles the multiple
- command enable. The CMDCHR equate determines the command separator
- character. A ';' has been chosen as the separator character in this
- distribution version.
-
- Comments are allowed on a command line. When the comment separator
- character is encountered as the first character of a command, the
- remainder of the line is ignored. The COMCHR equate determines the
- comment separator character. A ';' has been chosen as the separator
- character in this distribution version. Here is an example containing
- comments and multiple commands on a single line:
-
- A>get 100 junk;peek 100;;this is a comment.
- A>;this is also a comment.
-
- There exists a built-in search path for transient commands. First, the
- current drive/user is searched. Next, the current drive/default user
- is searched. Last, drive A/default user is searched. The DEFUSR
- equate determines the default user number, currently set to user 0 in
- this distribution version. The default user is temporarily changed
- with the DFU command. If a drive is specified in the transient
- command, the current and default user areas on the specified drive are
- searched. If a user number is specified, that user area on the current
- and default drive are searched. If both the drive and user number are
- specified, no search is performed. The same drive/user area is never
- searched twice.
-
- Transient commands are always "called." If a program terminates via a
- return rather than a warm boot, subsequent multiple commands on the
- command line are executed. Any program exiting by a warm boot reloads
- ZCPR and the subsequent commands lost.
-
- A default command can be placed in the command buffer and control
- passed to ZCPR for processing. The only thing required, besides
- placing the command in the buffer and jumping to CPRLOC, is to
- initialize the command character counter at the start of the buffer.
- The procedure is compatible with the original DRI CCP default command
- processing. If ZCPR is entered at CPRLOC+3 jump, default command
- processing is suppressed. Either way, register C must contain a valid
- drive/user, just like the original CCP.
-
-
- Submit File Processing
- ======================
-
- A basic design choice had to be made in the design of ZCPR concerning
- the execution of submit files. The original CCP had a problem. It
- ALWAYS looked for the $$$.SUB file on drive A and the submit program
- would place it on the current default drive. When the you were logged
- onto drive B and you issued a submit command, the $$$.SUB was placed on
- drive B and not executed.
-
- After much debate it was decided to have ZCPR perform the same type of
- function as CCP (look for the $$$.SUB file on drive A), but the problem
- with SUBMIT.COM still exists. Hence, RGF designed SuperSUB and RLC
- took his SuperSUB and designed SUB from it; both programs are set up to
- allow the selection at assembly time of creating the $$$.SUB on the
- default drive or on drive A. If you don't have one of these newer
- submit programs, a procedure for patching the standard SUBMIT.COM has
- been included at the end.
-
- The fixed drive choice permits a submit file to contain a series of
- commands exactly as they would be entered from a CP/M console. This
- permits things like:
-
- A>dir
- A>b:
- B>dir
-
- to be executed, even though the currently default drive is changed
- during execution. If the $$$.SUB file were present on the default
- drive, the above series of commands would not work. ZCPR would be
- looking for $$$.SUB on the default drive, and switching default drives
- without moving the $$$.SUB file would cause processing to abort. Note
- that the same problem occurs if the user number of the $$$.SUB file is
- not predefined. ZCPR assumes that the $$$.SUB file is located on user 0
- of drive A.
-
- The trick of using the $ flag returned by the BDOS disk reset is used
- to speed the search for a $*.* file on drive A. This trick will not
- work if the $$$.SUB file were located on another drive.
-
- The '>' prompt character is replaced by a special character while a
- submit file is in execution. The SPRMPT equate defines this special
- character, currently set to '$' in this distribution version.
-
-
- Command Syntax
- ==============
-
- Multiple commands can be placed on one line. If the comment character
- is encountered where a command should start, the rest of the line is
- ignored. Any command can be renamed by editing the command table.
- Command names can be up to eight characters long and are terminated by
- bit 7 high. If there is a conflict between an internal ZCPR command
- and a transient program of the same name, the internal command is
- executed. Type the command with the du: included if the external
- transient command is the one desired. Here is a complete alphabetized
- list of all the resident commands with their syntax:
-
- =============================================================================
-
- Command: BELL
-
- Function: To ring terminal bell.
-
- Forms: BELL
-
- Options: None.
-
- Uses: This command is designed to be placed in a submit file to
- ring the bell to indicate significant checkpoints.
-
- =============================================================================
-
- Command: BOOT
-
- Function: To execute BIOS cold boot routine.
-
- Forms: BOOT
-
- Options: REBOOT equate controls the inclusion/exclusion of this command.
-
- Uses: Reboots the system without pushing the reset button. The
- cold boot entry point in the BIOS must be supported for this
- command to work.
-
- =============================================================================
-
- Command: DFU
-
- Function: To set the Default User Number for transient commands.
-
- Forms: DFU <usrnum>
-
- Options: DEFUSR equate defines the default user choice until this
- command is entered.
-
- NUMBASE equate defines the character that specifies a
- hexadecimal number. The distribution version is set to 'H'.
-
- Uses: The default user area is searched after a transient command
- cannot be found in the current user area. If the transient
- command still has not been found, the default user on the
- default drive is searched last. The new default user number
- is in decimal, but hexadecimal numbers are entered by
- appending an 'H'. The next warm boot will restore the
- original default user number.
-
- =============================================================================
-
- Command: DIR
-
- Function: To display a directory listing of the files on a drive.
-
- Forms: DIR <afn> Display the DIR files
- DIR <afn> S Display the SYS files
- DIR <afn> B Display both DIR and SYS files
- DIR <afn> A Display both DIR and SYS files for all user areas
-
- Options: TWOCOL equate controls the number of columns in the display.
- Forty-column terminals are limited to two-column displays.
-
- WIDE equate controls the spacing between the columns and
- change the horizontal width of a directory display.
-
- FENCE equate specifies the character separator between the
- directory columns.
-
- USRDLM equate specifies the character between the user number
- and the filename.
-
- USRFLG, SYSFLG, and SOFLG equates specify the command line
- tail character that control the display of system and
- non-system files.
-
- Uses: Displays a directory listing of files in specific drive/user
- area.
-
- =============================================================================
-
- Command: ERA
-
- Function: To erase files.
-
- Forms: ERA <afn>
-
- Options: None.
-
- Uses: Deletes files. Names of erased files are displayed.
-
- =============================================================================
-
- Command: ERAQ
-
- Function: To erase files with individual query.
-
- Forms: ERAQ <afn>
- <afn>? y File erased
- <afn>? <CR> File not erased
-
- Options: None.
-
- Uses: Deletes a subset of a set of ambiguously specified files.
- Any answer other than 'Y' (either case) will cause the file
- to be skipped and not erased.
-
- =============================================================================
-
- Command: GET
-
- Function: To load the specified file from disk to the specified address.
-
- Forms: GET <hexadr> <ufn>
-
- Options: None.
-
- Uses: Loads a file into the TPA for patching purposes. This command
- searches for the specified file along the same search path as
- the transient command loader.
-
-
- =============================================================================
-
- Command: GO
-
- Function: To call the program in the TPA without loading from disk.
-
- Forms: GO <command tail>
-
- Options: None.
-
- Uses: Most useful to rerun a program already loaded into the TPA.
- Saves time and wear on disk drives. The command tail is
- entered exactly as it would appear if GO were replaced by the
- program name. Same as JUMP 100H, but more convenient,
- especially when used with parameters for programs like STAT.
-
- =============================================================================
-
- Command: JUMP
-
- Function: To call the program at a specified address.
-
- Forms: JUMP <hexadr> <command tail>
-
- Options: None.
-
- Uses: Executes code not located at 100H. For example, JUMP 0
- warm boots. The code must already reside at the specified
- address.
-
- =============================================================================
-
- Command: LIST
-
- Function: To print specified file on list device.
- -
- Forms: LIST <ufn> Print file
- LIST <ufn> P Print file without default paging
-
- Options: NLINEP equate determines the number of lines per page.
-
- FFKILL equate controls the suppression of form feeds before
- printable text.
-
- PGDFLG equate determines the command line tail character that
- toggles the default form feed insertion every NLINEP lines.
-
- NOSTAT equate controls the use of the BIOS list status call.
-
- Uses: Prints files with/without pagination on LST: device. A
- listing is aborted by a console ^C. Any submit file in
- process is terminated and control is returned gracefully to
- the console prompt.
-
- =============================================================================
-
- Command: PAGE
-
- Function: To eject a page on list device via a form feed.
-
- Forms: PAGE
-
- Options: NOSTAT equate controls the use of the BIOS list status call.
-
- Uses: Sends a form feed to the LST: device. The page eject can
- be aborted by a console ^C if the system hangs because the
- printer is not ready. If aborted, any submit file in process
- is terminated and control is returned gracefully to the
- console prompt.
-
- =============================================================================
-
- Command: PEEK
-
- Function: To display hex values beginning at a specified address.
-
- Forms: PEEK <hexadr> [<hexcnt>]
-
- Options: None.
-
- Uses: Displays hexadecimal values anywhere in the entire address
- space. The maximum value for <hexcnt> is 0FFH, but the
- default <hexcnt> is 256.
-
- =============================================================================
-
- Command: POKE
-
- Function: To poke a string of hex values into a set of consecutive
- addresses.
-
- Forms: POKE <hexadr> <hexval> [...<hexval>]
-
- Options: None.
-
- Uses: Modifies values anywhere in the entire address space. Each
- <hexval> represents one byte and is separated from the next
- by a space. The number of <hexval> are limited only by the
- size of the command line buffer. The address is incremented
- for each <hexval>. Excellent for hand patching code.
-
- =============================================================================
-
- Command: REN
-
- Function: To change the name of an existing file.
-
- Forms: REN <newufn>=<oldufn>
- REN <newufn>=<oldufn> Existing <newufn>
- Delete? y File deleted
-
- Options: None.
-
- Uses: Changes the names of files. Any du: on <oldufn> is ignored;
- the optional du: is on <newufn>. If there already exists a
- <newufn>, the console is queried for conformation. Any
- response except 'Y' (either case) aborts the command, kills
- any submit file in process, and returns gracefully to the
- command prompt.
-
- =============================================================================
-
- Command: SAK
-
- Function: To pause until a key is struck.
-
- Forms: SAK
- ? <any key>
-
- Options: None.
-
- Uses: Pauses a submit file until a keystroke is entered. Any
- character other than a ^C will resume execution. A ^C kills
- the submit file, any commands remaining on the command the
- line are ignored, and control returns gracefully to the
- prompt.
-
- =============================================================================
-
- Command: SAVE
-
- Function: To save the contents of TPA onto disk as a file.
-
- Forms: SAVE <Number of Pages> <ufn>
- SAVE <Number of Records> <ufn> R
-
- Options: RECFLG equate determines the command tail character that
- specifies records rather than pages.
-
- NUMBASE equate defines the character that specifies a
- hexadecimal number. The distribution version is set to 'H'.
-
- Uses: Saves the TPA to a file. Records are 128 bytes long, pages
- are 256 bytes long. Number of pages or records is in
- decimal, but a hexadecimal number is entered by appending an
- 'H'. Saved area begins at 100H.
-
- =============================================================================
-
- Command: SCL
-
- Function: To force ZCPR to parse only a single command per line.
-
- Forms: SCL
-
- Options: MULTPL equate determines the inclusion/exclusion of this
- command and whether or not multiple commands are allowed.
-
- CMDCHR equate determines the character separating multiple
- commands.
-
- Uses: Some transient commands require the command separator in the
- command tail. This command turns off multiple command
- parsing so the entire command tail is sent to the transient
- program. Multiple command format is reset at the next warm
- boot. SCL toggles.
-
- =============================================================================
-
- Command: TYPE
-
- Function: To display specified file on console.
-
- Forms: TYPE <ufn> Display file
- TYPE <ufn> P Display file without default paging
-
- Options: NLINES equate determines the number of lines per screen.
-
- FFKILL equate controls the suppression of form feeds before
- printable text.
-
- PGDFLG equate determines the command line tail character that
- toggles the default form feed insertion every NLINEP lines.
-
- Uses: Displays files with/without pagination on CON: device. A
- display is aborted by a console ^C. If aborted, any submit
- file in process terminates and control returns gracefully to
- the console prompt. When page breaks are enabled, any
- console character except ^C will display the next page of
- text.
-
- =============================================================================
-
- Command: USER
-
- Function: To change current user number.
-
- Forms: USER <usrnum>
-
- Options: SUPRES equate controls the display of the user number in the
- prompt when the user number is zero.
-
- MAXUSR equate controls the maximum allowable user number.
-
- NUMBASE equate defines the character that specifies a
- hexadecimal number. The distribution version is set to 'H'.
-
- Uses: This command changes the current user number. The new user
- number is in decimal, but a hexadecimal number is entered by
- appending an 'H'. This command has been retained for
- compatibility purposes only. It is far easier to change
- disk/user by typing du:.
-
- =============================================================================
-
-
- Error Messages
- ==============
-
- If any error is encountered as a command line is being parsed, a
- message will be printed and, for serious errors, the remainder of the
- line is ignored. Below is a complete list of all ZCPR error messages.
- Any error message encountered that is not on this list came from some
- program other than ZCPR.
-
- "?"
-
- An error was detected in the command. The an item on the command
- line was not what was expected. The command line is echoed up to
- the position where the error was detected, as close as can be
- determined, and the "?" printed. Any commands remaining on the
- command the line are ignored and any $$$.SUB file erased.
-
- "Full"
-
- If ZCPR was attempting to load a transient program, one of two
- things has gone wrong: either the program is so large that it won't
- fit into the TPA or a read error was returned from the BDOS. If
- ZCPR was attempting to save a file, the BDOS write call returned
- failure. Either the disk or the directory is full. Any commands
- remaining on the command line are ignored and any $$$.SUB file
- erased.
-
- "No File"
-
- No file could be found matching the filename specified in the
- command. This message is also be printed if the BDOS read command
- returns failure. If ZCPR was looking for a transient command, any
- commands remaining on the command line are ignored and any $$$.SUB
- file erased.
-
- "Name Error"
-
- The specified filename has a user number larger than the allowable
- maximum or an ambiguous filename was entered where only an
- unambiguous filename is permitted. Any commands remaining on the
- command line are ignored and any $$$.SUB file erased.
-
- "Delete?"
-
- Not really an error, but there already exists a file with the same
- name as the requested new name in the REN command. Any response
- except 'Y' (either case) aborts the command, any commands remaining
- on the command line are ignored, and any $$$.SUB file erased.
-
- "All?"
-
- Not really an error, but a check to verify that all files on the
- drive/user area are to be erased. Any response except 'Y' (either
- case) aborts the command and any commands remaining on the command
- line are ignored.
-
-
- Installation Instructions
- =========================
-
- 1) The first task is to determine the location of your BDOS because you
- MUST set the P2DOS equate to this value. If you do not know the
- location of your BDOS, use ZCPRDEMO to find it. If you do not
- already have ZCPRDEMO.COM, assemble ZCPR with the TEST equate true
- to make it. A bootstrap loader will be included and you can run the
- .com file. This program assembles without errors using Microsoft's
- M80/L80:
-
- A>m80 =zcpr
- A>l80 zcpr,zcprdemo/n/e
-
- Other assemblers can be used, but ZCPR.MAC will probably require
- editing to convert it to a form compatible. The major decision in
- converting is to determine how the .PHASE pseudo is to be handled.
- Probably the best solution to the .PHASE is to generate a .hex
- file and load it with an offset using DDT/SID/ZSID. Consult the
- "r" command in the DDT/SID/ZSID manaul.
-
- Run ZCPRDEMO and peek at low memory:
-
- A>zcprdemo
- A<peek 0 10
- 0000 C3 03 F2 00 00 C3 06 E4 00 00 00 00 00 00 00 00
- A<^C
-
- Notice the prompt character has changed from a '>' to a '<'. This
- tells you the special debug version of ZCPR is running. See the
- debug section at the end for details. Address 0 contains a jump 3
- beyond the start of the BIOS and address 5 contains a jump 6 beyond
- the start of the BDOS.
-
- Be careful if you attempt to execute a transient program from
- ZCPRDEMO. Some transient programs, like NSWP, return rather than
- warm boot when done. These programs don't know that ZCPRDEMO is at
- address 8000H rather than just under the BDOS. If they overwrite
- ZCPRDEMO, then the return is to random code. Of course, this is not
- a problem when ZCPR is installed just under the BDOS.
-
- 2) You MUST edit the code to place your BDOS/P2DOS/Z80DOS/ZRDOS start
- address in the P2DOS equate. Set COMLD true (and TEST false if you
- set it true in step 1 above) and make ZCPR.COM. A bootstrap loader
- will be included.
-
- Assuming you successfully assemble it, just type "zcpr" to run it.
- However, every time there is a warm boot, it will be replaced by
- the boot track CCP. If you like what you see, place a copy on the
- boot track to make it available all the time.
-
- 3) Reassemble, this time with COMLD false to make ZCPRNBLD.COM (ZCPR
- No Boot LoaDer).
-
- 4) Run SYSGEN to load a copy of the boot track into memory.
-
- B>; Sample terminal session for integrating ZCPR
- B>sysgen
- SYSGEN VER 2.2
- SOURCE DRIVE NAME (OR RETURN TO SKIP)a
- SOURCE ON A, THEN TYPE RETURN <cr>
- FUNCTION COMPLETE
- DESTINATION DRIVE NAME (OR RETURN TO REBOOT) <cr>
-
-
- 5) Run SAVE to save a track image to a file (eg: SAVE 32 BOOTFILE).
- The number on the save command depends on the size of your boot
- track loader; it can be as small as 31 and as large as 44. If you
- have extra disk space or are not sure, play it safe and use 44.
-
- B>save 44 cpm56.com <-- We now have a SYSGEN image of CP/M
-
- 6) Find the location of the stock CCP by peeking at the boot file. It
- is normally located at address 980H in the file. Using ZCPR:
-
- B>zcpr <-- Reload zcpr.com version
- B>get 100 cpm56.com
-
- and search for the start of the console processor:
-
- B>peek 980
- 0980 C3 xx xx C3 xx xx 7F 00 43 4F 50 59 52 49 47 48
- 0990 54 20 ...
-
- If you don't find the start of the CCP at 980H, don't be
- discouraged. It is there, but at a higher address. Keep looking.
-
- 7) When you find the location of the CCP, patch it with the new ZCPR
- image.
-
- B>get 980 zcprnbld.com
-
- 8) Place the new file onto the boot track of a test disk, not your
- original, using SYSGEN, and try it out.
-
- B>sysgen
- SYSGEN VER 2.2
- SOURCE DRIVE NAME (OR RETURN TO SKIP) <cr> <-- Use memory image
- DESTINATION DRIVE NAME (OR RETURN TO REBOOT)b <-- Load onto drive B
- DESTINATION ON B, THEN TYPE RETURN <cr>
- FUNCTION COMPLETE
- DESTINATION DRIVE NAME (OR RETURN TO REBOOT) <cr>
-
- You should now have a ZCPR system boot disk. Notice you did all
- your work on drive B so you wouldn't destroy the original.
-
-
-
- This may seem like a great number of steps, but each is only a single
- CP/M command line, total time is only 5 minutes or so after you get
- ZCPR to run as a .com file.
-
-
- Debugging ZCPR
- ==============
-
- Special provisions have been make to ease the debugging of ZCPR.
- Setting the TEST equate true causes the assembler to build a version of
- ZCPR that executes in the TPA. This allows the use of a debugger like
- DDT, ZSID, or Z8E to load and monitor execution. To identify the debug
- version, the prompt character is changed from '>' to '<' when it runs.
-
- CPRLOC for the test version is 8000H. A bootstrap loader is included
- at the beginning to move the image to this address. Do not try to set
- a breakpoint until after the loader has moved ZCPR. The easiest way to
- accomplish this is to single-step through the loader and then set your
- breakpoints. Change the execution address to something lower if 8000H
- does not leave enough space for the debugger.
-
- A small amount of code is also added at the end of the debug version to
- compute the BIOS list status and cold boot entry points at run time.
- This permits the demo version to execute properly without setting the
- BDOS location equate.
-
- Patching SUBMIT.COM
- ===================
-
- SUBMIT.COM is patched to run with ZCPR by the following procedure.
- This is recommended if the user does not have one of the newer public
- domain versions of submit. This patch simply makes SUBMIT.COM always
- place the $$$.SUB file on drive A. Illustrative terminal session
- follows:
-
- A>get 100 submit.com;peek 5bb 2
- 05BB 00 24 <-- Patch is at 5BB Hex
- A>poke 5bb 1 <-- Change 0 (default drive) to 1 (drive A)
- A>peek 5b0 20 <-- Let's check just to make sure
- 05B0 00 00 00 00 00 00 30 30 31 20 24 01 24 24 24 20
- 05C0 20 20 20 20 53 55 42 00 00 00 1A 1A 1A 1A 1A 1A
- A>save 5 newsubmt.com <-- Save new SUBMIT.COM file
-
- Pretty simple, huh?