Introduction

Welcome to the File Download Archive, your gateway to the Emulator.ca Systems software library.

In the early 1980s, something remarkable happened. Programmers began giving away their work -- not because they had to, but because they wanted to share what they had created with fellow enthusiasts. This "shareware" movement transformed software distribution. Instead of waiting for shrink-wrapped boxes to appear in computer stores, users could download programs directly from bulletin boards, try them, and register the ones they found useful.

The File Download Archive connects you to this tradition. Our library contains games, utilities, programming tools, and documentation -- all available for immediate download. Some programs are freeware, given freely with no strings attached. Others are shareware, offered for evaluation with a request that you send the author a registration fee if you continue using the software. (Please honour these requests. The shareware system works because users support the programmers who make it possible.)

Every file in this archive has been tested on EC-series hardware and scanned for known viruses before being added to the library. Our SysOps personally verify that programs work as described. When you download from this BBS, you can trust what you are getting.

What You Will Find

• GAMES -- From text adventures to arcade action, entertainment for every taste
• UTILS -- Disk utilities, file managers, compression tools, and system enhancers
• DOCS -- Tutorials, reference guides, and technical documentation

The collection grows regularly as users upload their own creations and SysOps acquire new releases. Check back often -- you never know what treasures might appear.

Quick Start

Ready to download your first file? Follow these steps:

1. Dial the File Download Archive: ATDT555-0603
2. Select a file: Type its number and press ENTER
3. Choose XMODEM: Press X at the file options screen
4. Wait for transfer: Watch the block counter climb to completion

+--------------------------------------------------+
|  QUICK START EXAMPLE                             |
+--------------------------------------------------+
|  ATDT555-0603                                    |
|  CONNECT 1200                                    |
|                                                  |
|  ╔══════════════════════════════════════════════╗ |
|  ║        FILE DOWNLOAD ARCHIVE                 ║ |
|  ║                                              ║ |
|  ║  XMODEM file transfers supported             ║ |
|  ╚══════════════════════════════════════════════╝ |
|                                                  |
|  Directory: /ROOT                                |
|                                                  |
|  1. [DIR] DOCS                                   |
|  2. [DIR] GAMES                                  |
|  3. [DIR] UTILS                                  |
|  4. [FIL] BBS.TXT                   xxx bytes    |
|  5. [FIL] README.TXT                xxx bytes    |
|                                                  |
|  [U]pload file  [Q]uit                           |
|  Choose: 5                                       |
|                                                  |
|  Selected: README.TXT                            |
|  Size: xxx bytes                                 |
|                                                  |
|  [X]MODEM download                               |
|  [V]iew file                                     |
|  [B]ack to listing                               |
|                                                  |
|  Choice: X                                       |
|                                                  |
|  XMODEM Download: README.TXT                     |
|  Blocks: 5  Bytes: 640  (100%)                   |
|  Download complete!                              |
+--------------------------------------------------+

That's all there is to it! Read on for detailed instructions on navigating the file library, viewing files inline, and uploading your own contributions.

Getting Connected

To access the File Download Archive, configure your modem and dial:

ATDT555-0603

Upon successful connection, you will see the archive banner and root directory listing:

Terminal Requirements

For optimal operation, configure your terminal as follows:

Browsing Files

Understanding the Directory Display

Each directory listing shows the current path and available items:

Directory: /GAMES

 1. [FIL] HELLO.BAS                xxx bytes

 2. [..] Parent Directory

[U]pload file  [Q]uit
Choose: _

Entry Types

Navigation

Navigating the File Download Archive is straightforward:

• Enter the number of a directory to enter it
• Enter the number of a file to view its options (download, view, or go back)
• Enter the number for [..] to return to the parent directory
• Enter U to upload a file via XMODEM
• Enter Q to quit and disconnect

File Categories

The archive is organised into directories by type. Here is what you will find in each:

GAMES

Software and code samples for your EC-series or IBM PC-compatible system.

UTILS

System utilities and essential tools for DOS computing.

DOCS

Documentation, tutorials, and reference materials.

Root Directory Files

General information available at the top level:

Downloading Files

The File Options Screen

To download a file, first enter its number when viewing a directory. Rather than starting the transfer immediately, the archive presents a file options screen:

From this screen you have three choices:

XMODEM Download

Press X to begin an XMODEM file transfer. The archive will display the filename and size, then wait for your terminal's XMODEM receiver to send the initial handshake character (C). Once the handshake completes, data flows in 128-byte blocks with CRC error checking.

The progress line updates in place as each block is transferred, showing the running count of blocks, bytes sent, and percentage complete.

Turbo Mode

At 300 baud, even a small file can take a while. During any XMODEM transfer (download or upload), press T to toggle Turbo mode, which increases the transfer speed by 10x. Press T again to return to normal speed.

Turbo mode ENABLED

This is a convenience feature of the emulated modem -- real 1980s hardware offered no such luxury!

Viewing Files

Press V at the file options screen to display the file contents directly on your terminal. The text is shown between delimiter lines:

After viewing, you are returned to the file options screen, where you can proceed with an XMODEM download or go back to the listing.

Transfer Time Estimation

Planning your download session? Use this table to estimate how long transfers will take at various baud rates (without Turbo mode):

With Turbo mode enabled, divide these times by ten.

The XMODEM Protocol

The File Download Archive uses XMODEM-CRC, the enhanced variant of Ward Christensen's original 1977 protocol. Data is sent in 128-byte blocks, each verified with a 16-bit CRC checksum. If a block arrives corrupted, the receiver requests retransmission automatically -- making XMODEM reliable even over noisy phone lines.

The protocol handshake works as follows:

1. The archive announces the transfer and waits
2. Your terminal's XMODEM receiver sends C to request CRC mode
3. The archive sends data in 128-byte blocks, each with a CRC
4. Your terminal acknowledges each block with ACK (or NAK to retry)
5. The archive signals completion with an EOT character

Uploading Files

The File Download Archive is not merely a one-way repository. You can contribute your own files using the Upload feature.

Starting an Upload

From any directory listing, press U to begin an upload. The archive will prompt you for a filename:

Upload Steps

1. Press U at the directory listing
2. Enter a filename (up to 20 characters). The name is automatically converted to uppercase. Characters other than letters, digits, periods, hyphens, and underscores are stripped.
3. Start your terminal's XMODEM send. The archive sends the initial C handshake to begin CRC-mode reception.
4. Your terminal sends data in 128-byte blocks; the archive acknowledges each one.
5. Upon completion, the file is saved to the current directory.

Press ENTER with an empty filename to cancel the upload and return to browsing.

Turbo mode (T) works during uploads as well, just as it does for downloads.

File Information

File Extensions

Common file types you will encounter in the archive:

Understanding File Sizes

File sizes are displayed in bytes. Quick reference:

• 1 KB (Kilobyte) = 1,024 bytes -- small text file
• 10 KB = 10,240 bytes -- medium program or document
• 32 KB = 32,768 bytes -- typical utility program
• 64 KB = 65,536 bytes -- maximum .COM file size
• 360 KB = one 5.25" DSDD floppy disk
• 720 KB = one 3.5" DD floppy disk

Command Reference

Directory Listing Commands

The following inputs are accepted at the Choose: prompt while browsing:

File Options Commands

The following inputs are accepted at the Choice: prompt after selecting a file:

Transfer Commands

During an XMODEM transfer (download or upload):

Special Keys

System States

The file browser operates in four states:

Modem Signals

The File Download Archive uses the following RS-232 control signals:

When you select Q to quit, the system will:

1. Display the farewell message
2. Deassert DTR and RTS signals
3. Initiate hangup procedure

Troubleshooting

Common Issues

"Invalid choice" message

You entered a number outside the valid range. Check the directory listing and enter only numbers that correspond to displayed items. If the screen shows items 1-5, entering "6" will produce this error.

Garbled box characters

Your terminal may not support IBM PC extended ASCII. The menu headers and borders will appear as random characters, but the actual file listings remain readable. Try switching your terminal to VT100 mode, or simply ignore the cosmetic issue.

Transfer appears stuck

Large files take time at low baud rates. A 32KB file at 300 baud takes approximately 18 minutes -- that is normal. Watch the block counter for any movement at all. If the block count has not changed in 60 seconds, you may have a stalled connection. Try pressing T to enable Turbo mode for faster transfers.

Disconnected during transfer

This is the most frustrating problem, and unfortunately the most common. Possible causes:

1. Call waiting interrupted the connection. Disable it before dialing with *70 (on most phone systems).
2. Phone line noise. Try again later, especially during off-peak hours when line quality is better.
3. Modem timeout. Some modems disconnect after a period of "silence" even during an active transfer. Check your modem's S-registers.
4. Someone picked up an extension. This immediately kills modem connections.

Downloaded file does not work

• .ZIP files: You need PKZIP/PKUNZIP to extract them. Download PKZIP.EXE from UTILS first.
• .BAS files: These require the SLP-BASIC interpreter (dial 555-0300).
• Wrong system type: A program compiled for one computer will not run on another. Check the file description.

Appendix A: Quick Reference Card

+============================================================+
|          FILE DOWNLOAD ARCHIVE QUICK REFERENCE             |
+============================================================+
|                                                            |
|  DIAL: ATDT555-0603                                        |
|                                                            |
|  DIRECTORY LISTING (Choose: prompt)                        |
|  ----------------------------------                        |
|  1-99     Select numbered item (directory or file)         |
|  U        Upload a file via XMODEM                         |
|  Q        Quit and disconnect                              |
|                                                            |
|  FILE OPTIONS (Choice: prompt)                             |
|  -----------------------------                             |
|  X        Download file via XMODEM                         |
|  V        View file contents on screen                     |
|  B        Back to directory listing                        |
|                                                            |
|  DURING XMODEM TRANSFER                                    |
|  -----------------------                                   |
|  T        Toggle Turbo mode (10x speed)                    |
|                                                            |
|  DISPLAY INDICATORS                                        |
|  ------------------                                        |
|  [DIR]    Directory - enter to browse contents             |
|  [FIL]    File - select for options                        |
|  [..]     Parent directory link                            |
|                                                            |
|  TRANSFER TIMES (approximate, normal speed)                |
|  ------------------------------------------               |
|             300 baud    1200 baud    2400 baud             |
|  1 KB       35 sec      9 sec        4 sec                 |
|  8 KB       4.5 min     1 min        35 sec                |
|  32 KB      18 min      4.5 min      2 min                 |
|                                                            |
+============================================================+

Appendix B: Glossary

Archive -- A compressed file containing one or more files, such as .ZIP or .ARC format. Requires an extraction utility to access contents.

Baud -- A measure of signaling rate; in most modem contexts, equivalent to bits per second. Common rates are 300, 1200, and 2400 baud.

BBS -- Bulletin Board System. A computer running software that allows remote users to dial in, leave messages, and transfer files.

Checksum -- A value calculated from file data used to verify that a transfer completed without errors.

COM file -- A directly executable DOS program file, limited to 64KB in size.

CRC -- Cyclic Redundancy Check. A more reliable error-detection method than simple checksums.

DTE/DCE -- Data Terminal Equipment / Data Communications Equipment. Your computer is the DTE; the modem is the DCE.

EXE file -- An executable DOS program file that can exceed the 64KB limit of COM files.

Flow Control -- A mechanism to pause data transmission when the receiver's buffer is full. Hardware flow control (RTS/CTS) is more reliable than software (XON/XOFF).

Freeware -- Software distributed at no cost, though the author retains copyright.

Protocol -- A defined method for transferring data, such as XMODEM or ZMODEM.

Shareware -- Software distributed freely for evaluation; users who continue using it are expected to pay a registration fee.

SysOp -- System Operator. The person who runs and maintains a BBS.

Turbo Mode -- An emulator convenience feature that accelerates XMODEM transfers by 10x. Toggled with the T key during a transfer.

XMODEM -- A file transfer protocol developed by Ward Christensen in 1977. Sends data in 128-byte blocks with error checking. The File Download Archive uses the XMODEM-CRC variant with 16-bit CRC checksums.

See Also

After downloading software, explore these related services:

• SLP-BASIC (555-0300) -- Run .BAS files you download from the GAMES directory
• SLP-FORTH (555-0400) -- Forth programming environment for advanced users
• Editor (555-0730) -- Read and edit .TXT documentation files
• Chat Lounge (555-0705) -- Discuss downloads with other users, get recommendations
• Email System (555-0750) -- Contact shareware authors about registration