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The first version of the Aster consisted of four " Eurocard's ", one Z80 CPU card with 64KB memory, one Motorola MC6845 based video card, one double density floppy disk controller card and one " keyboard / RS232 / cassette interface " card.
Plus a " backplane card ", ( which connected all the other cards ) and a keyboard.
And was intended for hobbyists, to be sold as a kit consisting of the parts and the PCB's for the computer and attached keyboard.
After selling a few kits, MCP became convinced there was a much bigger market for an improved model sold as a completed working system.
However the original kit version lacked many features that prevented its use as a serious computer system.
Because the original designer had left the company another employee completely redesigned most of the system, ( adding a display snow remover circuit, true 80 / 64 column text mode support, ( with different size letters for TRS-80 and CP / M mode, so that in TRS-80 mode the full screen was also used, not just a 64x16 portion of the 80x25 screen ) with an improved font set ( adding " gray scale " version of the TRS-80 mozaik graphics and many special PETSCII like characters ), and a more flexible and reliable floppy disk controller and keyboard interface plus many other small improvements ), also an enclosure was developed for the main computer system, ( in the form of a 19-inch rack for the Eurocards ) and for two floppy disk drives and the power supply.
A software engineer was hired to write the special " dual boot mode " BIOS and the special CP / M BIOS.
The " dual boot mode " BIOS actually discovered whether a TRS-DOS, or Aster CP / M disk was placed in the drive, and would, depending on the type of disk, reorganise the internal memory architecture of the system, to either be 100 % TRS-80 compatible or optimally support CP / M, with as much " workspace " as possible, and the 80x25 video mode.
It also was responsible for switching to ROM BASIC when the system was turned on with the break key pressed, and later supported a primitive LAN system, using the RS232 port with modified cabling.
The very first of the ready made computers were sold with the " kit " versions of the euro cards, the version with redesigned cards came a month or so later.

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