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

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.

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.

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.

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.

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

    read_byte()

      do

        wait a while

      while((read_status_port AND 1) equals 0)

      read in the input_data_port

      return the data read in



    write_byte()

      do

        wait a while

      while((write_status_port AND 1) equals 0)

      output data to output_data_port

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.

The board address is fixed at #150.

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.

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.

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.

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

 

Installation

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