Transtech Transputer, Руководство пользователя

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Host Computer Interface
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Transputer Motherboard User Manual TMB M 711
• Writing a 1 into bit 0 of SubsystemAnalyseLatch asserts
subsystemAnalyse ;
• Writing a 0 into bit 0 of SubsystemAnalyseLatch deasserts
subsystemAnalyse ;
• Reading a 1 from bit 0 of SubsystemErrorLatch indicates that
subsystemError
is TRUE;
• Reading a 0 from bit 0 of SubsystemErrorLatch indicates that
subsystemError
is FALSE;
The subsystem is reset/analysed under control of the transputer on
the TRAM. However, the subsystem must be reset when the TRAM
is reset. As already described the following combinational logic is
used to propagate the subsystem signals:
• SubsystemReset = UpReset OR SubsystemResetLatch
• SubsystemAnalyse = UpAnalyse OR SubsystemAnalyseLatch
• SubsystemError does NOT propagate
Because of filtering on the motherboard it is recommended that when
resetting/analysing subsystems the corresponding signal is held
asserted for at least 5 ms. In the case of reset, the subsystem should
be left for a further 5 ms before attempting to boot it.
3.4 Host Computer Interface
Most motherboards have an interface to a host computer. The host
supplies file services and terminal IO to application programs
running on the transputer network. Clearly the structure of the host
interface is not generic - the remainder of this section discusses the
standard PC interface for PC AT machines and clones. This interface
is commonly referred to as a “B004” interface.
3.4.1 Host IO Space
In PC machines interface hardware is mapped into a special address
space called the IO space. The driver program running on the PC
uses this address space to talk to the add-in card.
The module motherboard employs a block of addresses within the IO
space.It is possible to locate the base of this block at one of a number
of places in this address space so as to prevent conflicts with other
add-in cards. By default the base address is150 hex.