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AMSTRAD PC3386SX

AMSTRAD PC3386SX (52 KBytes)
The AMSTRAD PC3386SX, a member of their (rather unsuccessful) PC-series. Although it makes use of standard PC components, it contains some clever solutions, such as a CPU daughterboard. Also see the keyboard closeup
(picture copyright by M.A.Grundke)

Specifications

Name AMSTRAD PC3386SX

Made by AMSTRAD Consumer Electronics plc

Released 1990

Serial-No.
AMSTRAD PLC MODEL:PC3386SX
SERIAL NO 04200316-C8-310411/EU-G
MADE IN U.K.
keyboard: 548-0852636

Board-info
DPA1704 [ ]
AMSTRAD Z70921
MADE IN THE U.K.
ISSUE C
030490
also see the board overviews

CPU Intel NG80386SX-20 (C-stepping)
the 80386SX was a 80386 with address-bus reduced to 24 bit. This made it easy to integrate into existing, cheap 286-boards. Intel also used the '386' to imply advanced technology, trying to fight 286-clones (e.g. from AMD)

CPU is located on a CPU-daughterboard, together with a FPU socket
early PC3386SX (like this one) came with 64K CPU cache; in later machines, it was omitted (cost-reduction?)

Speed
20 MHz
can be slowed down to 10, 6 or even 4 MHz via keyboard-command

RAM
1024 KBytes:
4 pcs. Samsung KMM 59256AN-10 (256KB, 9 bit SIMM)

all four 30 pin SIMM sockets must be fitted (=32 bit bandwidth)
the machine can also use 1 MB/ 4 MB SIMMs, allowing a total of 16 MB RAM (which is the maximum address-range in 286/ 386SX-design)
this particular machine came with 9 bit parity SIMMs. Not sure whether this was necessary or not (e.g. the later 4386 required parity RAM)

ROM/ Native OS AMSTRAD PC3386SX BIOS v2.1 (128KB)
DALLAS DS1287 RTC
stored in 4 pcs. ST27256-20CP (32Kx8 EPROMS)
this PC3386SX BIOS seems to be an AMSTRAD-development. Later machines (e.g. MegaPC) came with Quadtel ROM-BIOS
the 2000/ 3000-series' BIOS does not contain a SETUP-utility, like that of later PCs. Boot-parameters have to be set with a DOS-program (SETUP.EXE) instead. They are then stored in the RTC's non-volatile RAM
machine came with Microsoft-DOS 3.30 as OS

Keyboard/ Layout 102 keys/ german (QWERTZ) layout
although using a standard DIN connector, the AMSTRAD PC3386SX requires an AMSTRAD-compatible keyboard (and a special mouse, if the front mouse-port is used). This was true for all AMSTRAD PCs prior to the 5000-series, which was the first to make use of PS/2 peripherals
also see the keyboard closeup

Graphics Paradise PVGA1A-JK VGA-controller
inmos IMSG171P-35G RAMDAC
256 KByte VRAM:
8 pcs. Texas Instruments TMS4464-12NL (32Kx8 SRAM)

Display modes:
320x200, 256 colors (MCGA)
640x480, 16/ 256 colors (VGA)
640x400, 256 colors ('Paradise extended mode')
800x600, 2/ 16 colors ('Paradise extended mode')
the non-standard modes can be disabled via DIP-switch
Paradise controllers were manufactured by Western Digital. Popular successors to the PVGA1A were WD90C00 and WD90C11

Sound integrated 0.25W, 8 Ohm speaker
there's even a volume-knob for it at the machine's front!

Media Zilog Z0765A08PSC FDC (floppy-disk controller)
SED9420C data separator
Samsung SFD-321B diskdrive
3.5" disks, 720KB (PC-DD)/ 1440 KB (PC-HD)
FDC can also control a 2nd diskdrive
Seagate ST157A AT-bus harddisk
44.7 MB formatted capacity (57 MB unformatted)
spin time: 3600 RPM
geometry: 560 cylinders, 6 heads
form-factor: 3.5" full-height

the PC3386SX supports up to two AT-bus drives
AMSTRAD's SETUP-utility (see ROM) only knows of pre-defined harddisk types (can become a problem when adding or replacing harddisks)

Input/ Output SiS 82C450 UART
DS1488M serial line driver
2x DS1489AM serial line receivers
AMSTRAD 40230 (function unknown, DMA-controller?)
AMSTRAD 40231 (function unknown, bus-controller?)
Toshiba T4758A (function unknown, PIC?)
Toshiba T9035H (function unknown)
DS1013M-15, D51000M-100 (function unknown)
ISA expansion slots:
1x 8 bit, 2x 16 bit on mainboard
1x 8 bit, 2x 16 bit on ISA daughterboard

the daughterboard occupies one of the onboard 16 bit slots
34 pin internal floppy connector
40 pin internal AT-bus connector
1x 9 pin SUB-D AMSTRAD mouse port (front; not a serial!)
6 pin DIN AMSTRAD keyboard connector (non-standard)
1x 25 pin parallel port
1x 25 pin SUB-D serial port (RS232)
15 pin SUB-D VGA output
standard power outlet (for monitor) & power receptacle

Miscellaneous
The PC3386SX was the first AMSTRAD-PC to make use of standard components for cost-reduction (e.g. the case). But there are still 'AMSTRAD specialties', such as the mouse- and keyboard, the useful CPU board and ISA backplane
Overview of the 3000-series:
PC3086. 8086 @8MHz, 640K RAM, onboard-VGA, XT-bus controller

PC3286. 80286 @16MHz, 1 MB RAM, onboard-VGA, AT-bus controller. Most likely same mainboard as PC3386SX (can somebody confirm this?)
PC3386SX. 80386SX @20MHz, 64K CPU-cache (early machines only), 1/ 4 MB RAM, onboard-VGA, AT-bus controller
Sinclair APC 3386SX. Same as AMSTRAD PC3386SX, but with slightly modified case. One of the many machines sold under Sinclair brand, after AMSTRAD had bought the rights to use it in 1986

Predecessors, successors:
PC1512 (aka Sinclair PC800). 8086 @8MHz, 512K, CGA onboard
PC1640 (aka PC6400). 8086 @8MHz, 640K, EGA onboard
PC20 (aka Sinclair PC200). PC1512-board in a keyboard case
PPC512/ PPC640. Similar to PC1512 (512K/ 640K), portable case
1000-series. PC1286 and PC1386 known to exist
2000-series. Configurations similar to 3000-series (2086/ 2286/ 2386), but the 2386 featured a 80386DX-CPU. Came in a stylish (non-standard) case
4000-series: Like 3000-series, smaller case (new board)
5000-series: Like 4000-series, but with the ability to use PS/2-compatible keyboards and mice. Also introduced a 486-machine, the PC5486 (80486SLC CPU)
6000-series: PC6486 (486SX) known to exist. WD90C11 VGA
7000-series: PC7386 (80386SX), PC7486 (80486SX). WD90C11
8000- and 9000-series: 80486DX- (PC8486/ 9486) and Pentium-CPUs, PCI (PC9555i)

'Intel' is a registered trademark of the Intel Corporation. 'MS-DOS' is a registered trademark of Microsoft Corporation. 'MCGA' and 'VGA' are registered trademarks of International Business Machines (IBM). All other content, including pictures is (C) M.A.Grundke (aka Sothius), unless otherwise noted. Unauthorized copying or usage of that content, without former permission from M.A.Grundke or the rightful copyright-holder, is prohibited

Sothius' Home - Museum - AMSTRAD - AMSTRAD PC3386SX - additional pictures

Name	AMSTRAD PC3386SX
Made by	AMSTRAD Consumer Electronics plc
Released	1990
Serial-No.	AMSTRAD PLC MODEL:PC3386SX SERIAL NO 04200316-C8-310411/EU-G MADE IN U.K. keyboard: 548-0852636
Board-info	DPA1704 [ ] AMSTRAD Z70921 MADE IN THE U.K. ISSUE C 030490 also see the board overviews
CPU	Intel NG80386SX-20 (C-stepping) the 80386SX was a 80386 with address-bus reduced to 24 bit. This made it easy to integrate into existing, cheap 286-boards. Intel also used the '386' to imply advanced technology, trying to fight 286-clones (e.g. from AMD) CPU is located on a CPU-daughterboard, together with a FPU socket early PC3386SX (like this one) came with 64K CPU cache; in later machines, it was omitted (cost-reduction?)
Speed	20 MHz can be slowed down to 10, 6 or even 4 MHz via keyboard-command
RAM	1024 KBytes: 4 pcs. Samsung KMM 59256AN-10 (256KB, 9 bit SIMM) all four 30 pin SIMM sockets must be fitted (=32 bit bandwidth) the machine can also use 1 MB/ 4 MB SIMMs, allowing a total of 16 MB RAM (which is the maximum address-range in 286/ 386SX-design) this particular machine came with 9 bit parity SIMMs. Not sure whether this was necessary or not (e.g. the later 4386 required parity RAM)
ROM/ Native OS	AMSTRAD PC3386SX BIOS v2.1 (128KB) DALLAS DS1287 RTC stored in 4 pcs. ST27256-20CP (32Kx8 EPROMS) this PC3386SX BIOS seems to be an AMSTRAD-development. Later machines (e.g. MegaPC) came with Quadtel ROM-BIOS the 2000/ 3000-series' BIOS does not contain a SETUP-utility, like that of later PCs. Boot-parameters have to be set with a DOS-program (SETUP.EXE) instead. They are then stored in the RTC's non-volatile RAM machine came with Microsoft-DOS 3.30 as OS
Keyboard/ Layout	102 keys/ german (QWERTZ) layout although using a standard DIN connector, the AMSTRAD PC3386SX requires an AMSTRAD-compatible keyboard (and a special mouse, if the front mouse-port is used). This was true for all AMSTRAD PCs prior to the 5000-series, which was the first to make use of PS/2 peripherals also see the keyboard closeup
Graphics	Paradise PVGA1A-JK VGA-controller inmos IMSG171P-35G RAMDAC 256 KByte VRAM: 8 pcs. Texas Instruments TMS4464-12NL (32Kx8 SRAM) Display modes: 320x200, 256 colors (MCGA) 640x480, 16/ 256 colors (VGA) 640x400, 256 colors ('Paradise extended mode') 800x600, 2/ 16 colors ('Paradise extended mode') the non-standard modes can be disabled via DIP-switch Paradise controllers were manufactured by Western Digital. Popular successors to the PVGA1A were WD90C00 and WD90C11
Sound	integrated 0.25W, 8 Ohm speaker there's even a volume-knob for it at the machine's front!
Media	Zilog Z0765A08PSC FDC (floppy-disk controller) SED9420C data separator Samsung SFD-321B diskdrive 3.5" disks, 720KB (PC-DD)/ 1440 KB (PC-HD) FDC can also control a 2nd diskdrive Seagate ST157A AT-bus harddisk 44.7 MB formatted capacity (57 MB unformatted) spin time: 3600 RPM geometry: 560 cylinders, 6 heads form-factor: 3.5" full-height the PC3386SX supports up to two AT-bus drives AMSTRAD's SETUP-utility (see ROM) only knows of pre-defined harddisk types (can become a problem when adding or replacing harddisks)
Input/ Output	SiS 82C450 UART DS1488M serial line driver 2x DS1489AM serial line receivers AMSTRAD 40230 (function unknown, DMA-controller?) AMSTRAD 40231 (function unknown, bus-controller?) Toshiba T4758A (function unknown, PIC?) Toshiba T9035H (function unknown) DS1013M-15, D51000M-100 (function unknown) ISA expansion slots: 1x 8 bit, 2x 16 bit on mainboard 1x 8 bit, 2x 16 bit on ISA daughterboard the daughterboard occupies one of the onboard 16 bit slots 34 pin internal floppy connector 40 pin internal AT-bus connector 1x 9 pin SUB-D AMSTRAD mouse port (front; not a serial!) 6 pin DIN AMSTRAD keyboard connector (non-standard) 1x 25 pin parallel port 1x 25 pin SUB-D serial port (RS232) 15 pin SUB-D VGA output standard power outlet (for monitor) & power receptacle
Miscellaneous	The PC3386SX was the first AMSTRAD-PC to make use of standard components for cost-reduction (e.g. the case). But there are still 'AMSTRAD specialties', such as the mouse- and keyboard, the useful CPU board and ISA backplane Overview of the 3000-series: PC3086. 8086 @8MHz, 640K RAM, onboard-VGA, XT-bus controller PC3286. 80286 @16MHz, 1 MB RAM, onboard-VGA, AT-bus controller. Most likely same mainboard as PC3386SX (can somebody confirm this?) PC3386SX. 80386SX @20MHz, 64K CPU-cache (early machines only), 1/ 4 MB RAM, onboard-VGA, AT-bus controller Sinclair APC 3386SX. Same as AMSTRAD PC3386SX, but with slightly modified case. One of the many machines sold under Sinclair brand, after AMSTRAD had bought the rights to use it in 1986 Predecessors, successors: PC1512 (aka Sinclair PC800). 8086 @8MHz, 512K, CGA onboard PC1640 (aka PC6400). 8086 @8MHz, 640K, EGA onboard PC20 (aka Sinclair PC200). PC1512-board in a keyboard case PPC512/ PPC640. Similar to PC1512 (512K/ 640K), portable case 1000-series. PC1286 and PC1386 known to exist 2000-series. Configurations similar to 3000-series (2086/ 2286/ 2386), but the 2386 featured a 80386DX-CPU. Came in a stylish (non-standard) case 4000-series: Like 3000-series, smaller case (new board) 5000-series: Like 4000-series, but with the ability to use PS/2-compatible keyboards and mice. Also introduced a 486-machine, the PC5486 (80486SLC CPU) 6000-series: PC6486 (486SX) known to exist. WD90C11 VGA 7000-series: PC7386 (80386SX), PC7486 (80486SX). WD90C11 8000- and 9000-series: 80486DX- (PC8486/ 9486) and Pentium-CPUs, PCI (PC9555i)