Model 5540
(386 class) Reference & Diagnostic Disk for 5530-S,T/5540-T/5550-S,T,V v1.50 (DOS/V) Reference Disk for 5530-S,T/5540-T/5550-S,T,V v1.50 (DOS/V) Diagnostic Disk for 5530-S,T/5540-T/5550-S,T,V v1.50 (DOS/V) Reference & Diagnostic Disk for 5530/5540/5545/5550/5570 v1.36 (JDOS)
40REF135.EXE Reference Disk for 5540-T v1.35 (JDOS)

General Information
Hard Disk interface
System Overview

PS/55 5540-T

General Information

5541 was released after 5550-S/T/V and it looks like PS/2 Model 53. (I do not know the inside layout of Model 53). This machine can't take any Display Adapter other than the Display Adapter B-II as its video sub-system.

Model 5540-T Brochure


Ref. ver. 1.00 to 1.36 are based on JDOS.
Ref. ver. > 1.4x are based on DOS/V.

Ref. ver. 1.50 covers most 386 models such as 5550-S/T/V, 5570-T/V, 5540-T, 5530-T.


Display Adapter B-2 was used for this model. VGA chip is not provided on the planar.

Noticed that the display adapter seen HERE is not a B-II but more looks like V (AVEC). Don't know for sure if it's a B (BVEC) or perhaps some member of the AVEC family.

(PS/55Z 5510-T, which is very similar to 5540, can be configured with XGA /A.)


2MB23F3270, 59F9046, 79F2566

Hard Disk interface

Same as 8570 ESDI (more or less).

5540-T Planar (386DX 20 MHz)

Outline by Mr. Tahara (FIBMJ # 4 member). Edited by Major Tom.

Y1 14.31818 MHz
Y2 24.000 MHz
Y3 40.000 MHz
U8 NS16550AV NS16550
U9 90X9298 8042
U11 35F3489 ADDR GA
U12 65F0082 EPP-3
U17 33F5838 I/O GA
U22 35F3489 DATA GA
U25 33F5946 CPU GA
U26 i80386 (DX)
U27 90X8134 DMA Controller
U29 79F1016 MEM GA
U32 FPU???? 80387
U34 N828077AA FDD controller
U37 65F0155 (BIOS EPROM)
J8 MCA Riser with ESDI connector
J9 Memory Riser Slot
J10 FDD connector (34-pin)
J14 72-pin SIMM slot
J13 Power? 8-pin (or SP?)
J16 Power? 7-pin
J7 Main Power Connector (10-pin)

System Overview

<-- Rear view

<-- Inner View

One SIMM slot J14 is placed on the planar and additional 2 slots are provided through SIMM riser card which goes to connector J9.

A bus riser for J8 connector has MCA card slots on the left side and an ESDI HDD DB 2 connector is on the right side.

I/O connectors are placed as outline shows (Cable connectors are plugged in vertically).

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Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 25 Jun 2022 - Changes & Credits | Legal Info & Contact