Gigatron TTL
| Gigatron screenshot collage.webp | |
| Manufacturer | Marcel van Kervinck and Walter Belgers |
| Type | Home computers |
| publication | March 2018 |
| End of production | 19th |
| Factory price | € 149.50 |
| processor | 74xx -TTL chips |
| random access memory | 32 KB CMOS - SRAM |
| graphic | 60 × 120 pixels @ 59.98 Hz VGA , 64 colors |
| Sound | 4 channel 6 bit |
| Disk | EPROM |
| operating system | own emulation |
The Gigatron TTL is an 8-bit - microcomputer in retro style, the processor exclusively by 74xx - TTL is constructed chips instead of a completed CPU or the hardware to the state of reproduction of the start of the arcade game era . Target groups for the kit computer are computer enthusiasts, for teaching and hobby purposes.
architecture
The CPU is implemented by a small set of chips from the TTL chips of the 74xx series and is operated with a clock frequency of 6.25 MHz , but can be overclocked with faster chips , as can the RAM.
Three CPU modes have been implemented:
- 8 bit assembler , implements a Harvard architecture . This mode offers a 17- command set and supports up to 256 commands: 8 ALU operations , 8 addressing modes and 4 bus modes . The operating system and the BASIC interpreter are written in 8-bit assembler.
- 16-bit vCPU interpreter that implements a Von Neumann architecture and has a 34 command set. This loads and starts programs from the RAM . The integrated programs are written for this vCPU.
- MOS-6502 emulator (experimental), is supposed to execute the MOS-6502 machine language .
The video technology is generated by the "emulated" CPU and supports an image resolution of 160 × 120 pixels with 64 colors. Since the program execution and graphics rendering are carried out by the vCPU, the screen contains black (empty) scan lines when saving. Processor time for programs; it can be configured by the user to give better graphics or more CPU time to programs.
The sound is also generated by the vCPU 4 channels with 6 bits.
software
The programs are contained in the ROM chip and written in GCL ( Gigatron Control Language ), BASIC or vCPU.
The following programs are included:
- Snake
- Racer, a pole position- like game.
- Almond bread .
- Pictures , a picture viewer for the pre-installed pictures.
- Tetronis, a Tetris clone.
- Bricks, a breakout clone.
- TicTacToe, a Tic-Tac-Toe written in BASIC in text mode
- BASIC, a Tiny BASIC interpreter.
- WozMon, a Woz monitor
- Loader, function for loading the vCPU or BASIC programs via the joystick port.
- Credits, shows the credits in the text that change the colors.
With the Tiny-BASIC-Interpreter programs can be created, the system parameters changed and programs can be loaded into the non-volatile memory of the integrated keyboard controller and saved there.
The supplied software is licensed under Clause 2 of the BSD license .
Assembly kit
The microcomputer is sold as a kit and includes:
- The printed circuit board ( PCB) .
- The required 74xx -TTL chips
- A replaceable EPROM with a socket for firmware updates
- (upgradeable to a 64 KB chip)
- Game controller and VGA ( D-SUB ) connections.
- USB port and cable for power supply.
- A game controller similar to the NES .
- The keyboard controller with built - in non-volatile memory .
- The resistors, capacitors and diodes
- A set of 4 customizable LEDs
- manual
- A wooden box for presentation and assembly
The kit does not contain a keyboard nor non-volatile memory . A keyboard controller, which can be connected to the game controller port, comes with a small built-in non-volatile memory to store the BASIC programs. An Arduino Die-Card can be programmed to interact between the computer and the microcomputer, both for programming and as additional memory.
Availability
The kit is available for € 149.50. The updates are provided via a new ROM chip that is delivered as an update and should be changed manually.
There is also an emulator available online that can be used to load precompiled vCPU and Tiny BASIC programs.
Individual evidence
- ↑ Gigatron kits are shipping! | Details | Hackaday.io ( en )
- ↑ Mike Barela: The Gigatron - a TTL microcomputer without a microprocessor #VintageComputing # 8bit ( en-US ) In: Adafruit Industries - Makers, hackers, artists, designers and engineers! . December 5, 2018. Retrieved April 15, 2019.
- ↑ Data sheets - Gigatron ( en-US ) Retrieved January 2, 2020.
- ↑ FAQ - Gigatron ( en-US ) Accessed January 2, 2020.
- ↑ Adding 6502 support | Details | Hackaday.io ( en ) In: hackaday.io . Retrieved January 3, 2020.
- ↑ By: Emulating A 6502 In ROM ( en-US ) In: Hackaday . July 3, 2019. Accessed January 2, 2020.
- ↑ Gigatron! The TTL computer as a kit | Details | Hackaday.io ( en ) In: hackaday.io . Retrieved April 15, 2019.
- ↑ Gigatron TTL microcomputer ( en-US ) In: HomeComputerMuseum . Accessed January 2, 2020.
- ↑ Gigatron emulator . In: gigatron.io . Retrieved April 15, 2019.