When a CMPP is reset, the EC unit will create a PD with
the PD number to be 0, named PD[0]. PD[0] is used to drive
the user’s main program to run. The layout of PD[0] is as
follows.
The PN field is 0 standing for the number of the main
program is 0. The value of the field named UN/OP Sequence
is ”PM/R0,ID/D0” , which means the PD will firstly
go to the PM unit to request a reading instruction operation
and save the fetched instruction into the field TB0, and
then the PD will go to the ID unit to request a decoding
operation. Note that a functional unit will delete the first
UN/OP pair of the field named UN/OPseq of a PD after the
functional unit has finished the service for that PD, which
makes the second UN/OP pair to be now become the first
UN/OP pair, so that the PD is able to know where it should
go and what service it should request next.
To make shorter, this paper only select four instructions
to be the examples to show how a CMPP works.
Suppose a SUB instruction is of the form: SUB
R6,R5,R4 which means R6→[R5]-[R4], and a PD has gone
to the PM unit requesting a instruction fetching service and
returned with the SUB instruction in its TB0 field, and now
the PD reaches the ID unit requesting a decoding service.
After the ID unit has done the decoding service for the PD,
the result of the PD’s fields is as follows.
When a CMPP is reset, the EC unit will create a PD with
the PD number to be 0, named PD[0]. PD[0] is used to drive
the user’s main program to run. The layout of PD[0] is as
follows.
The PN field is 0 standing for the number of the main
program is 0. The value of the field named UN/OP Sequence
is ”PM/R0,ID/D0” , which means the PD will firstly
go to the PM unit to request a reading instruction operation
and save the fetched instruction into the field TB0, and
then the PD will go to the ID unit to request a decoding
operation. Note that a functional unit will delete the first
UN/OP pair of the field named UN/OPseq of a PD after the
functional unit has finished the service for that PD, which
makes the second UN/OP pair to be now become the first
UN/OP pair, so that the PD is able to know where it should
go and what service it should request next.
To make shorter, this paper only select four instructions
to be the examples to show how a CMPP works.
Suppose a SUB instruction is of the form: SUB
R6,R5,R4 which means R6→[R5]-[R4], and a PD has gone
to the PM unit requesting a instruction fetching service and
returned with the SUB instruction in its TB0 field, and now
the PD reaches the ID unit requesting a decoding service.
After the ID unit has done the decoding service for the PD,
the result of the PD’s fields is as follows.
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