Transtech Transputer, Руководство пользователя

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The TMB16 Motherboard
TMB M 711 Transputer Motherboard User Manual
133
9.6.3 Operation of the Software
The functioning of the interface is controlled by software running on
the T2. The software is provided on the TMB16 in non-volatile
memory (EPROM). Essentially, the software exploits the available
hardware to provide an invisible connection between the PC and the
transputers mounted on the motherboard. So as to maintain
backwards compatibility with older motherboards, this connection is
actually between the PC and link0 of TRAM module0.
At the beginning of any data communication the two processors must
agree on the amount of data to be transferred. This is achieved by
transmitting a single 16 bit counter. That counter determines the
number of bytes that follow. In occam, this protocol may be defined
as:
INT16::[]BYTE
i.e. the same as the iserver protocol. Note that the hardware limits
the maximum amount of data that can be transferred in one block to
32KBytes (see the memory map).
As far as the T2 transputer is concerned, access to the PC is
achieved by reading/writing its external memory. During a data
transfer from the PC to the transputer network the T2 is reading from
its external memory and writing data to one of its links. This is
achieved with the transputer channel
out
instruction. Similarly,
during a data transfer from the transputer network to the PC, the T2
is reading data from a link and writing this data to its external
memory, which is achieved with the transputer channel
in