Crum unit mountable in consumable unit of image forming apparatus and image forming apparatus using the same

An apparatus which is at least one of an image forming apparatus and an image reading apparatus, the apparatus comprising:

• a main controller configured to control operation of the apparatus;
• a consumable unit;
• and
• a customer replacement unit monitor (CRUM) unit configured to store information of the consumable unit,
• wherein the main controller transmits first clock signals having a first frequency in a data section in which data signals are transmitted from the apparatus and received by the CRUM unit and a second frequency on an idle section in which the data signals are not transmitted from the apparatus and received by the CRUM unit, and
• the CRUM unit converts the first clock signals into second clock signals maintaining a first or second value in the idle section, the first value being higher than the second value, and processes the data signals by using the second clock signals.

A customer replacement unit monitor (CRUM) unit mountable in or on an apparatus, the CRUM unit comprising:

• a clock converter configured to receive first clock signals from the apparatus and to convert the received first clock signals into second clock signals;
• a memory configured to store data related to a consumable unit which is consumed by operation of the apparatus;
• and
• a controller configured to manage the memory based on the second clock signals and data signals transmitted from the apparatus and received by the CRUM unit,
• wherein the first clock signals are divided into a data section an idle section, the first clock signals having a predetermined first frequency in the data section and having a predetermined second frequency or maintaining a constant value in the idle section, and
• the second clock signals are clock signals maintaining a first or second value in the idle section, the first value being higher than the second value.

A customer replacement unit monitor (CRUM) unit mountable in or on an apparatus, the CRUM unit comprising:

• a decoder configured to receive, from the apparatus, first clock signals incompatible with I2C protocols and divided into a data section and an idle section with the first clock signals having a predetermined first frequency in the data section and a predetermined second frequency or maintaining a constant value in the idle section, and to convert the received first clock signals into second clock signals having a data section and an idle section and being compatible with I2C protocols;
• a memory configured to store data related to a consumable unit which is consumed by operation of the apparatus;
• and
• a controller configured to manage the memory based on data signals transmitted from the apparatus and received by the CRUM unit, and on the second clock signals.

A customer replacement unit monitor (CRUM) unit mountable in or on an apparatus, comprising:

• a memory configured to store data related to a consumable unit that is consumed by operation of the apparatus;
• at least one of a decoder and a power extract circuit to extract power from first clock signals received by the CRUM unit from the apparatus, the first clock signals being converted inside the CRUM unit into second clock signals which are different from the first clock signals;
• and
• a processor to manage the memory based on the second clock signals and on data signals received by the CRUM unit from the apparatus,
• wherein the extracted power is used by at least one of the processor and the memory.