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Sundance SMT004A-2 4 Slot PC/ISA TRAM Motherboard


The SMT004A-2 is a low-cost, 4 slot TRAM motherboard designed to accommodate up to 4 transputer modules within a PC/ISA slot and normally occupies a single half-length expansion slot. The SMT004A-2 offers ’Plug-and-go’ system integration, with a wide range of TRAMs available from Sundance and other companies. Guaranteed compatibility enables system integrators to easily configure bespoke solutions to embedded computing problems. In additions, systems may be installed simply by replacing one or more of the motherboard’ on-board TRAMs.

The SMT004A-2's interface enables the PC to reset, analyze and communicate with a network of TRAMs. Links 0 and 3 of each TRAM site is connected to a 40-way strip.

Reset/Analyze/Error signals of each TRAM site can be connected to the Up signal from another transputer signal or connected to the PC bus. Slot 1 has a sub-system port and these signals may be used to control the remaining TRAMs. Up, Down and Sub-system signals are accessible from the 40-way strip connector. PC addresses #150 is used for the 8-bit bus interface.

Programmable Registers

On the SMT004A-2 there is a set of software registers that perform various control functions required for link communication. They also allow the user to control the status of external transputer networks.

PC Registers

These registers are mapped as an IO port. The base value is fixed at #150.

Port IO Map
Address Register
Base+0 Input Data Register ( ro )
Base+1 Output Data Register ( wo )
Base+2 Input Status Register ( rw )
Base+3 Output Status Register ( rw )
Base+16 Error Register ( ro )
Base+16 Reset Register ( wo )
Base+17 Analyse Register ( wo )
Input Data Register, Output Data Register

These two registers are located inside the C011 chip. The functions of the input and output data registers are reasonably self explanitory. When the status registers indicate that they are either ready to receive valid data, or they contain valid data then the data is written to or read from these registers.

Input and Output Status Register

These registers are contained in the C011 chip and indicate the status of the input and output data registers.

Input status
rd Bit 0 0 no input data
    1 valid input data
wr Bit 1 0 disable input int
    1 enable input int
Output status
rd Bit 0 0 output busy
    1 output ready
wr Bit 1 0 disable output int
    1 enable output int
Reset, Analyse, and Error

The source and desitination of the Reset, Analyse and Error signals is determined by the presence of the resistors LS4 and LS5. For more details refer to the Sub-system control section.

Error Registers

The error status is a software readable port that indicates the Error status of the external transputer network. It can either be the error line from the error pin on Slot 1, or the UpNotError line from the 40-way patch area on the board.

Error Register
rd Bit 0 0 Error false
    1 Error true
Reset Registers

You can write to this register to control the state of the PCNotReset line on the 40-way patch area. This can then be used to control an external transputer network. Normally these signals are fed back onto the SMT004A-2 to control any TRAMs that are fitted.

Reset Register
wr Bit 0 0 Reset false
    1 Reset true
Analyse Registers

You can write to this register to control the state of the Analyse line of the onboard transputer, or the PCNotAnalyse line on the 40-way patch area.

Analyse Register
wr Bit 0 0 Analyse false
    1 Analyse true
Example Code

This small piece of psuedo-code demonstrates how to access the data registers on the PC Bus.



        wait a while

      while((read_status_port AND 1) equals 0)

      read in the input_data_port

      return the data read in



        wait a while

      while((write_status_port AND 1) equals 0)

      output data to output_data_port

Control Configuration

The SMT004A-2 is designed to be a very low-cost board, and as such all options are pre-configured in the factory by using surface mount resistors. These functions can be changed by the user if required, or may be returned to the factory for modification.

Board Address

The board address is fixed at #150.

Link Speeds

Inmos links are capable of operation at two speeds. There are two sets of resistor pads which allow the user to select the link speed of the bus interface and the TRAMs independently. LS1 and LS2 are a row of three pads with resistor being fitted to the centre pad and either the top or bottom pad.

C011 Link Speed
LS1 LS2 Speed Comment
Out Out N/A Does not function
Out In 10MBit/s Factory default
In Out 20MBit/s  
In In N/A Does not function
TRAM link speed
LS6 LS7 Speed Comment
Out Out 20MBit/s  
Out In N/A Does not work
In Out N/A Does not work
In In 10MBit/s Factory default
Subsystem Control

The Motherboard is designed so that TRAM slots 1, 2, 3 and 4 can be controlled from a variety of sources. For slot 0 there is the option of being Reset and Analysed by either the PC interface or the Up control lines. The choice is determined by the presence of resistors at LS4 and LS5. For the other 3 slots there is the choice of being Reset and Analysed by either the Subsystem port on the first TRAM or the Down control lines.


Res.   Comment
LS4 In SubSystem active - factory default
  Out DownNot active
LS5 In PC interface active
  Out UpNot interface active

C011 Link Selection

Resister LS3 is be used to select the source and destination of the link information passed through the C011 link adapter. It can be set so that it sends information to, and receives information from the back connector, or TRAM slot 1. It has to be either one, or the other. It cannot be selected to be both.

Res.   Comment
LS3 In 40-way strip header
  Out Slot 1, factory default

40-way strip connector
Pin Signal Pin Signal  
1 Gnd 21 TRAM 4 Link 7 Out
2 UpNot Reset 22 TRAM 4 Link 7 In
3 UpNot Analyse 23 Gnd
4 UpNot Error 24 C011 Link In
5 NC 25 Pipe Head Link Out
6 NC 26 Pipe Head Link In
7 TRAM 1 Link 3 Out 27 SubSystem Not Reset
8 TRAM 1 Link 3 In 28 NC
9 Gnd 29 SubSystem Not Analyse
10 TRAM 2 Link 2 Out 30 SubSystem Not Error
11 TRAM 2 Link 2 In 31 Pipe Tail Link Out
12 TRAM 2 Link 3 Out 32 Pipe Tail Link In
13 TRAM 2 Link 3 In 33 NC
14 TRAM 3 Link 4 Out 34 NC
15 TRAM 3 Link 4 In 35 Down Not Reset
16 Gnd 36 Down Not Analyse
17 TRAM 3 Link 5 Out 37 Down Not Error
18 TRAM 3 Link 5 In 38 NC
19 TRAM 4 Link 6 Out 39 NC
20 TRAM 4 Link 6 In 40 C011 Link Out

To use pipe connections IC7 must be fitted (74BCT125)
LS3 selects C011 connection (PL1 or TRAM Link 0)


Add TRAMs to slot 1 of the SMT004A. The TRAM can be of any size up to a size 4 TRAM. It should have its identifying triangle aligned with the triangle marked on the SMT004A. If the Subsystem port is to be used (e.g., in an Inmos TDS system) then the module Subsystem pins should be carefully aligned with both the sockets provided in the Motherboard and the TRAM.

Any pin protectors fitted to the TRAM should be removed to prevent fouling the next slot of the PC, and nylon bolts should be fitted to prevent the TRAM from working loose. All TRAM pin 1 marker Triangles should be aligned with those on the SMT004A.

Having fitted the TRAMs to the SMT004A-2 as required, make any link connections between them before installing the assembly into the PC.

Remove all power from the PC, then open the case to expose the expansion slots. Choose a vacant slot that has sufficient space around it for any special TRAM modules or cables and remove the blanking plate from this slot, retaining the screw for fixing the SMT004A. Slide the SMT004A-2 into the relevant slot ensuring that the 'tail' of the card is in the card guide provided for it. Do not use excessive force.

When the SMT004A-2 is almost pushed fully home the gold fingers should be carefully aligned with the relevant connector in the PC and firmly pushed home. The fixing screw should then be fitted to retain the SMT004A-2 and any casings replaced on the PC.

Reapply power to the machine and switch on. The machine should boot normally. If it doesn't it probably means that there is an address clash somewhere. In this event call Sundance technical support to check that the values selected with the address jumpers are not clashing with existing cards.

Component Detail

Component Detail

Ident Function/Part Number
IC1 74F245
IC2 PAL22V10
IC4 74BCT125
IC5 74F14
IC6 PAL22V10
IC7 74BCT125
IC8 74BCT244
X1 5MHz Oscillator
DB9 9-way D-type connector
PL1 40-way strip header
LK1,2,3 Pipe jumpers
LK4 Terminator Jumper
J10 Custom Interface (Not Specified)

Feature Unit
Format PC/ISA  
Size Half card  
Number of module slots 4  
Module format TRAM  
Host interface 8-bits  
Sub-system logic Yes  
On-board processor No  
Peripheral logic No  
Length 165 mm
Width 105 mm
PCB thickness 1.5 mm
Comp. height above PCB 10 mm
Comp. height below PCB 0 mm
Storage temperature 0-70 °C
Operating temperature 0-50 °C
Weight 65 g
MTBF 674,000 Hours
Power supply voltage 4.75-5.25 V
Power consumption TBA W

Additional Details

The device is manufactured within the EU. Sundance Multiprocessor Technology is implementing BS5750 quality control procedures.

Sundance manufactures a range of standard and custom parallel processing products. The company strives to produce a comprehensive range of sub-system and system level products at high-quality and at a competitive price.

In line with a policy of continuous product development Sundance™ reserves the right to alter these specifications without prior notice. No responsibility can be accepted for loss or damage arising from the use of this product or documentation. Any comments on inaccuracies, omissions or structure of this document would be gratefully received via fax.

Sundance offers a 12 month warranty on this product. The terms of this warranty are that the product be returned to the manufacturer or distributor from which the product was purchased. Repair or replacement will be chargeable if the failure is as a result of either electrical or mechanical misuse.


Please contact Sundance to check that this revision of the engineering data is current with the latest revision of the printed page version.

User Manual & Support Software

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