⚠️ Disclaimer ⚠️
The software and resources provided here are experimental and unofficial. They are offered as-is, without warranty of any kind. Use at your own risk.
Purpose
The purpose of this tool is to create a blank mdv file for QL emulator.
⚠️ Experimental ⚠️
How to
Give a name and clic the button below.
DO NOT ADD the extention ".mdv"
Create the blank mdv file
MDV (Microdrive) Format - Sinclair QL
The MDV format is used to store data on Sinclair QL microdrives. An MDV file is structured into sectors, each containing a header and a data block. This format is compatible with emulators like QemuLator.
General Structure of an MDV File
- Total file size: 255 sectors × 686 bytes = 174,930 bytes.
- Write order: Sector 0 first, then sectors 254 down to 1.
Structure of a Sector (686 bytes)
1. Sector Header (hdr_t) - 28 bytes
| Offset (byte) | Size (bytes) | Description | Value/Example |
|---|---|---|---|
| 0 | 12 | Preamble (fixed header) | "QLAY MDV1 " |
| 12 | 1 | FF marker | 0xFF |
| 13 | 1 | Sector number | 0 to 254 |
| 14 | 10 | Medium name (padded with spaces) | "BLANK " |
| 24 | 2 | RND (arbitrary value) | 0x0000 |
| 26 | 2 | Header checksum (not calculated here) | 0x0000 |
2. Data Block (sector_t) - 658 bytes
| Offset (byte) | Size (bytes) | Description | Value/Example |
|---|---|---|---|
| 0 | 12 | BH Preamble (fixed header) | "QLAY DATA " |
| 12 | 1 | File type (0x00 = empty) | 0x00 |
| 13 | 1 | Block number within the sector | 0 to 254 |
| 14 | 2 | BH checksum (not calculated here) | 0x0000 |
| 16 | 8 | Data preamble | 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 |
| 24 | 512 | Data (filled with 0x00) | 0x00 |
| 536 | 2 | Data checksum (not calculated here) | 0x0000 |
| 538 | 120 | Extra bytes (filled with 0x00) | 0x00 |
Ressources
To do