Abstract: A clock supply method for supplying a clock to a plurality of processing units includes supplying a clock from a first clock supply unit to processing units forming a first group as a primary clock and to processing units forming a second group as a standby clock; supplying a clock from a second clock supply unit including a clock source different from that of the first clock supply unit to the processing units forming the second group as a primary clock and to the processing units forming the first group as a standby clock; and when a processing unit in the first or second group detects an abnormality of the primary clock, switching the standby clock into use in place of the primary clock being supplied to the processing units that has detected the abnormality belongs; wherein the first and second clock supply units supply clocks with the same frequency.

Abstract: A clock supply method for supplying a clock to a plurality of processing units includes supplying a clock from a first clock supply unit to processing units forming a first group as a primary clock and to processing units forming a second group as a standby clock; supplying a clock from a second clock supply unit including a clock source different from that of the first clock supply unit to the processing units forming the second group as a primary clock and to the processing units forming the first group as a standby clock; and when a processing unit in the first or second group detects an abnormality of the primary clock, switching the standby clock into use in place of the primary clock being supplied to the processing units that has detected the abnormality belongs; wherein the first and second clock supply units supply clocks with the same frequency.

Abstract: In an access processing system in an information processor, the information processor includes: an access device (10, 11) for generating an access request signal; an accessed device (13) provided with a memory means (30) that is accessed by the access device (10, 11); and an address bus (14) that has the access device and accessed device connected with the information processor at least by the address bus (14).The access processing system is processed such that, if an access request is produced, when the access request signal does not require all bits in the address bus (14), an unused bit in the address bus (14) is loaded with write data to deliver it to the accessed device (13).

Abstract: In a clock control circuit for suppressing a clock pulse in a plurality of devices which operate in synchronization with each other, the clock control circuit detects first and second clock suppress conditions, generates a first clock suppress signal in all the devices based on the detection of the first clock suppress condition, generates a second clock suppress signal in a particular device based on the detection of the first or second clock suppress conditions, transmits the clock suppress signals to all the devices, and suppresses the clock pulse in all the devices based on the first and second clock suppress signals. The second clock suppress signal suppresses the clock pulse after it is suppressed by the first clock suppress signal, and continues to suppress the clock pulse until a suppression release signal is received.