SAM Coupé is an 8-bit home computer released in the UK by Miles Gordon Technology (MGT) in 1989 . The computer could emulate the ZX Spectrum 48 and was positioned as an update for it.
|Type of||Home computer|
|Date of issue||1989 year|
|Produced by||1992 year|
|CPU||Z80 at 6 MHz|
|RAM||256 or 512 KB (expandable to 4.5 MB)|
|Data storage devices||audio cassette , floppy disk , SAM cartridge|
|OS||SAM BASIC , TR-DOS , CP / M|
- Processor: Z80B at 6 MHz
- RAM: 256 KB, possibly internal expansion up to 512 KB and external expansion up to 4 MB; memory in blocks of 16 KB was projected into four blocks of the processor's address space, switching through the input-output port
- Video Modes:
- 4 mode: 256 × 192, linear framebuffer, 4 bits per pixel (16 colors) = 24 KB
- mode 3: 512 × 192, linear framebuffer, 2 bits per pixel (4 colors) = 24 KB
- mode 2: 256 × 192, linear framebuffer, 1 bit per pixel, plus 32 × 192 individual attributes for each block 8 × 1 pixels = 12 KB
- mode 1: 256 × 192, individual attributes, non-linear framebuffer compatible with ZX Spectrum = 6.75 KB
- Sound: 6-channel stereo sound generated by Philips SAA 1099 chip
The SAM Coupé is built on the Z80B microprocessor, clocked at 6 MHz, and has an ASIC chip similar to ULA in the ZX Spectrum. The 64 KB address space available to the processor is divided into four 16 KB blocks, into which, using the I / O ports, various RAM blocks can be included. In the basic model, the board housed 256 KB of RAM, which could be increased to 512 KB; in addition, the memory could be increased by additional blocks of 1 MB, a maximum of 4 such blocks. The main data carrier was a compact cassette ; it was also possible to install one or two 3½-inch floppy drives in the case. The Philips SAA 1099 chip provided six-channel stereo audio with a range of 8 octaves.
ZX Spectrum Compatibility Mode
ZX Spectrum emulation was limited to emulating a version with 48 KB of memory. At the same time, a copy of the ZX Spectrum ROM was included in the lower 16 KB and the video switched to mode 1, in which the processor frequency decreased. ZX Spectrum ROM was not supplied with the machine, it had to be obtained from a real ZX Spectrum.
Since the processor speed was not exactly the same as in the original, the bootloaders did not work in some games. To solve this problem, a Messanger device was created that could save the memory status of the ZX Spectrum connected to it to a SAM Coupé drive. Messanger connected to the Spectrum expansion port and the SAM Coupé network port.
The ZX Spectrum 128 memory model is not compatible with the SAM Coupé memory model, sound chips are also different. However, it was possible to convert some games to work with SAM Coupé.