Many of us got our start in computers through a joint venture between Tandy and Radio Shack stores, the TRS-80. Joe Pasqua relives those days with a 40%-scale replica he built using 3D printing and a Raspberry Pi to emulate the ancient operating system. It even includes a cutout for a working keyboard and trackpad.
Pasqua designed the project to capture the feel of the TRS-80 Model 3 or Model 4 but acknowledges it’s not a replica. Instead, he’s incorporated his favorite aspects of each into the design. The project bears the most resemblance, cosmetically, to the TRS-80 Model 4.
The TRS-80 Micro Computer System was introduced in 1977 when Tandy launched it for sale in its Radio Shack stores. Initially, it used the popular Zilog Z80 processor, and several successors followed over the next few years. In 1983, the Model 4 got a faster Zilog Z80A CPU and a larger display.
The 3D-printable design includes a 5-inch 640x480 display and two decorative but non-functional floppy drives. The floppy drives have LEDs that can flash randomly to help convey the feel of the classic 1980s computer. The cutout below, where the original TRS-80 would include a keyboard, is designed to hold an inexpensive, off-the-shelf wireless keyboard and trackpad.
To turn this project from a 3D-printed decoration into something usable, Pasqua has incorporated a place inside the case to hold a Raspberry Pi. The maker says it can work with anything from a Raspberry Pi 3 Model B to the latest Raspberry Pi 5, but for his purposes, he’s using a Raspberry Pi 4.
You could run this as a Raspberry Pi microcomputer, but where’s the fun in that? Pasqua found an emulator to run the original TRSDOS operating system. The trs80gp emulator allows the Raspberry Pi to act as any model of TRS-80, from Model 1 to the later Color Computer.
