A GBA Cartridge Flash tool that operates using a Tang Nano 20K FPGA alongside a Windows client built with WinForms.
The Tang Nano 20K connects directly to the GBA cartridge socket, while ROM data is transferred using the UART protocol (COM via USB). The WinForms client enumerates available COM ports, lets the user select the appropriate serial port (typically the only available one), and proceeds to display the cartridge header. It then provides an option to download and save the entire ROM to disk.
The hardware operates by receiving commands via UART in the form of single bytes. The following table lists the available commands:
| Command | Description |
|---|---|
| 'h' (0x68) | Performs a dump of the header (192 bytes). |
| 'a' (0x61) | Downloads a 4MB ROM. |
| 'b' (0x62) | Downloads an 8MB ROM. |
| 'c' (0x63) | Downloads a 16MB ROM. |
| 'd' (0x64) | Downloads a 32MB ROM. |
Each command triggers an operation that prompts the hardware to read from the cartridge and send a specific amount of data through the UART to the client.
| GBAPak | GPIO PIN |
|---|---|
| A23 | 86 |
| A22 | 79 |
| A21 | 72 |
| A20 | 71 |
| A19 | 53 |
| A18 | 52 |
| A17 | 73 |
| A16 | 74 |
| A/D15 | 75 |
| A/D14 | 85 |
| A/D13 | 77 |
| A/D12 | 15 |
| A/D11 | 16 |
| A/D10 | 27 |
| A/D9 | 28 |
| A/D8 | 25 |
| A/D7 | 26 |
| A/D6 | 29 |
| A/D5 | 30 |
| A/D4 | 31 |
| A/D3 | 17 |
| A/D2 | 20 |
| A/D1 | 19 |
| A/D0 | 18 |
| WR | 51 |
| RD | 48 |
| CS | 55 |
| CS2 | 49 |