摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
An information processing system wherein a module to operate as a master which executes a read access to a module to operate as a slave requests a bus arbiter to afford the mastership of a bus with a bus mastership request signal, and it simultaneously asserts a last cycle signal so as to notify the bus arbiter of the fact that the next cycle will be the last cycle to be used by the master. Subsequently, when the master has had the use of the bus granted by a bus use grant signal from the bus arbiter, it transfers an address to the slave by the use of the bus in the next cycle, thereby starting the read access. After the read access, the master releases the bus mastership. Only when the slave has failed to accept the transferred address, does it assert a retry request signal two cycles after the transfer cycle of the address not accepted. In this case, the module having executed the transfer two cycles before the cycle of the asserted signal executes again the transfer executed before. Thus, the address to be transferred can be transferred to the module ready to accept the address, in only one cycle.
摘要:
In a data processing system, a plurality of modules connected to a system bus thereof are assigned with identifiers. When a source module initiates a split read access to another module, the source module sends an address of the access destination module and an identifier of the source module. When sending a response to the source module, the destination module returns response data and the identifier of the source module thereto. Checking the identifier from the destination module, the source module determines the response data returned as a response to the initiated access.
摘要:
In a data processing system, a plurality of modules connected to a system bus thereof are assigned with identifiers. When a source module initiates a split read access to another module, the source module sends an address of the access destination module and an identifier of the source module. When sending a response to the source module, the destination module returns response data and the identifier of the source module thereto. Checking the identifier from the destination module, the source module determines the response data returned as a response to the initiated access.
摘要:
In a data processing system, a plurality of modules connected to a system bus thereof are assigned with identifiers. When a source module initiates a split read access to another module, the source module sends an address of the access destination module and an identifier of the source module. When sending a response to the source module, the destination module returns response data and the identifier of the source module thereto. Checking the identifier from the destination module, the source module determines the response data returned as a response to the initiated access.