Sakhr AX-350
This page was last modified 00:32, 26 February 2019 by Gdx. Based on work by Mars2000you and Wild Penguin and others.

Contents

Description

Computer

Sakhr Computers was a Kuwaiti company (Al Alamiah co.) that was selling MSX computers imported from Japan in all of the Arab world. These MSX were localized and rebranded for some Arabic markets.

The AX-350 is the Yamaha YIS-604-128 or CX7M-128 localised by Al Alamiah. The mini-slot has been replaced by a floppy disk drive and the module slot has been removed. However, the internal structure is closer to the YIS-805/128.

Note that AX350 is printed on the front of the computer but many AX350 are indicated on the underside as AX-350II. The explanation lies in a very fast modification of the built-in firmware. See AX-350II for more details. The hardware is the same for both machines.

Brand Sakhr (Manufacturer: Yamaha)
Type AX-350
Year 1987
RAM 128kB in slot 3-2
VRAM 128kB
Media MSX cartridges, DD floppy disks
Video Yamaha V9938
Audio PSG (YM2149 integrated in MSX-Engine S1985)
Chipset Yamaha S1985
Extras Arabic BASIC, 720kB 3,5" floppy disk drive, Firmware (Arabic Writer, English Writer, The Painter)

Firmware

This machine comes with version 2.01 of Arabic firmware, present on all Sakhr/Al Alamiah computers. The firmware can be skipped by pressing CTRL key while booting and until you come on the MSX-BASIC screen. By doing that, the machine will be in International mode, the Arabic characters will not be available and also you get only one drive (the A: drive) even if you have added an external diskdrive.

This firmware adds Arabic characters, new MSX-BASIC commands (see Arabic BASIC) and 3 applications. You can choose them in the menu with the keys 1 to 3.

By comparison with version 1.01, the Calendar has been removed and the Graphics application replaced by the Arabic version of The Painter, a graphic tool in screen 5 (the original version can be found in the Yamaha YIS-805). Other options are two Word Processors, Arabic Writer and English Writer.

If you press key 4 when you are in the menu, you will go to MSX-BASIC. Going back to the menu is possible with CALL MENU or _MENU. From MSX-BASIC, THE PAINTER can be launched with CALL PAINT or _PAINT. (don't use these commands if you are in International mode !)

Pictures

Computer

Sakhr AX-350
Sakhr AX-350(II) back side
Sakhr AX-350 label
Sakhr AX-350(II) left side
Sakhr AX-350(II) inside
Sakhr AX-350(II) motherboard

Firmware

Arabic firmware version 2.01
Arabic firmware 2.01 menu
Arabic firmware Arabic Writer
Arabic firmware English Writer
Arabic firmware The Painter (Arabic version)
Arabic firmware The Painter (Arabic version)

Specifications

The AX-350 is a MSX2 with a Z80A from Zilog and an MSX-Engine S1985 from Yamaha. Floppy Disk Controller chip is the MB8877A.

Slot Map

Help needed
The below slot-map is an assumption, it needs to be checked on a real machine.
Slot Slot
0-0 0‑1 0-2 0-3 Slot 1 Slot 2 3-0 3-1 3-2 3-3
Page C000h~FFFFh Cartridge
Slot 1
Cartridge
Slot 2
Painter
ROM
128kB
Memory
Mapper
Page 8000h~BFFFh Arabic
ROM
Page 4000h~7FFFh Main-ROM Disk ROM
Page 0000h~3FFFh Sub-ROM

Connections

Upgrades

RAM upgrade

On this model the RAM can be relatively easily expanded to 256KB by adding four 4464 or compatible DRAM chips to the empty spots on the motherboard and bridging the jumper "-J-" (near IC305, LS670), and cutting a jumper trace and bridging another jumper, both immediately next to IC326. Former will connect the fourth bit to the mapper register (on the existing LS670) and the latter is required to connect MA17 to the LS139 (IC306) instead of pulling it low (which is correct for 128kb configuration).

The RAM expansion of 1024kB from Alexey is not supported.