Philips HCS 280
This page was last modified 17:06, 3 November 2021 by Mars2000you. Based on work by Rderooy and Gdx.



The Philips HCS 280 is a rare computer, it's a white version of the NMS 8280/00 machine, and is the same color as the Sanyo MPC-27, on which the design of the NMS 8280 is based.

The Philips logo and the reference HCS 280 appear only on the keyboard, there is no branding or product type on the main unit. As the MSX logo is also missing, we can say that it's an Hidden MSX, but when you boot the machine, there cannot be any doubt!!!. In the MSX Club Magazine 14 (page 8), in an interview with a Philips representative there is talk of launching such Hidden MSX systems under the HCS logo, they mention plans for a HCS 250 Telecomunications system which is actually a NMS 8250 with integrated telecom interface and color monitor. It is not known if the HCS 250 was actually brought to market.

This computer seems to have been used in Italy, Spain and The Netherlands in combination with other products to create teletext content. The letters HCS were also used by Philips for a monitor, the HCS 35, a Videotel terminal, the HCS 80, released in 1990, and for a teletext programmer, the HCS 121, released in 1987.

In 1988, Philips had released 2 other Videotel machines (NMS 3000 and NMS 4000), with a design similar to the 'MSX compatible' NMS 800 and NMS 801 computers.

Brand Philips (Manufacturer: Sanyo)
Model HCS 280
Year 1990
Region Europe
Launch price
RAM 128kB in slot 3-2
VRAM 128kB
Media MSX cartridges, 2DD floppy disks
Video Yamaha V9938
Audio PSG (YM2149 integrated in MSX-Engine S3527)
Chipset Yamaha S3527
Keyboard layout QWERTY + numeric keypad
Extras 2 720kB 3,5" floppy disk drives, reset button, video digitizer, superimposer, sliders to control the video, audio mix and digitize levels, button to select the input source, mouse
Emulation Emulated as Philips NMS 8280 in blueMSX - ROM dump needed probably only for checking. See this thread for details


Philips HCS 280 with HCS 35 monitor
Philips HCS 280 detail of keyboard
Philips HCS 280 detail of keyboard


The HCS 280 is an MSX2 with a Z80A from NEC (D780C-1) and an MSX-Engine S3527 from Yamaha.

This model is known for SCC (and other sound cards) mixing issues. There are several modifications fixing this, the opamp mod by Daemos and luppie not being the worst one.

Slot Map

Slot 0 Slot 1 Slot 2 Slot 3-0 Slot 3-1 Slot 3-2 Slot 3-3
Page C000h~FFFFh Cartridge
Slot 1
Slot 2
Page 8000h~BFFFh Mirror
Page 4000h~7FFFh Main-ROM Disk ROM
Page 0000h~3FFFh Sub-ROM Mirror
  • The 16KB Sub-ROM is mirrored over pages 0 to 3 in slot 3-0
  • The Disk ROM is a 16kB ROM - 4000h-7FFFh. However, the FDC registers are visible on all 4 pages.