Accessory apparatus, image-capturing apparatus and control method therefor

An accessory apparatus detachably attachable to an image-capturing apparatus, the accessory apparatus comprising:

• an accessory communicator configured to provide, with the image-capturing apparatus, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus;
• and
• an accessory controller configured (a) to, in response to receiving from the image-capturing apparatus through the notification channel a transmission request as the notice provided by a signal level of the notification channel being switched from a first level to a second level, transmit the accessory data to the image-capturing apparatus through the first data communication channel and (b) to receive the camera data transmitted from the image-capturing apparatus through the second data communication channel,
• wherein, when the image-capturing apparatus is configured to be capable of selectively performing (a) a first process to switch, after the accessory apparatus receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level and (b) a second process to keep, after the accessory apparatus receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level, the accessory controller is configured to, while the signal level of the notification channel is kept at the second level, transmit second accessory data as the accessory data different from the first accessory data to the image-capturing apparatus.

An image-capturing system including an image-capturing apparatus and an accessory apparatus detachably attachable to the image-capturing apparatus, the system comprising:

• a camera communicator included in the image-capturing apparatus and an accessory communicator included in the accessory apparatus, the camera and accessory communicators being configured to provide therebetween, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus;
• and
• a camera controller included in the image-capturing apparatus and an accessory controller included in the accessory apparatus, the camera controller being configured (a) to provide, by switching a signal level of the notification channel from a first level to a second level, a transmission request as the notice to the accessory controller to cause the accessory controller to transmit the accessory data to the camera controller through the first data communication channel and (b) to transmit the camera data to the accessory controller through the second data communication channel,
• wherein the camera controller is configured to be capable of selectively performing:
• a first process to switch, after the accessory controller receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level;
• and
• a second process to keep, after the accessory controller receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level, and
• wherein:
• the accessory controller is configured to, while the signal level of the notification channel is kept at the second level in the second process, transmit second accessory data as the accessory data different from the first accessory data to the camera controller;
• and
• the camera controller is configured to, while keeping the signal level of the notification channel at the second level in the second process, receive the second accessory data.

A control method of controlling an image-capturing apparatus to which an accessory apparatus is detachably attachable, the image-capturing apparatus providing, with the accessory apparatus, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus, the control method comprising the steps of:

• causing the image-capturing apparatus (a) to provide, by switching a signal level of the notification channel from a first level to a second level, a transmission request as the notice to the accessory apparatus to cause the accessory apparatus to transmit the accessory data to the image-capturing apparatus through the first data communication channel and (b) to transmit the camera data to the accessory apparatus through the second data communication channel,
• allowing the image-capturing apparatus to selectively perform:
• a first process to switch, after the accessory apparatus receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level;
• and
• a second process to keep, after the accessory apparatus receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level;
• and
• causing the image-capturing apparatus to, while keeping the signal level of the notification channel at the second level in the second process, receive second accessory data transmitted from the accessory apparatus as the accessory data different from the first accessory data.

A control method of controlling an accessory apparatus detachably attachable to an image-capturing apparatus, the accessory apparatus providing, with the image-capturing apparatus, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus, the control method comprising the steps of:

• causing the accessory apparatus (a) to transmit, in response to receiving from the image-capturing apparatus through the notification channel a transmission request as the notice provided by a signal level of the notification channel being switched from a first level to a second level, the accessory data to the image-capturing apparatus through the first data communication channel and (b) to receive the camera data transmitted from the image-capturing apparatus through the second data communication channel;
• and
• when the image-capturing apparatus is configured to be capable of selectively performing (a) a first process to switch, after the accessory apparatus receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level and (b) a second process to keep, after the accessory apparatus receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level, causing the accessory apparatus to, while the signal level of the notification channel is kept at the second level, transmit second accessory data as the accessory data different from the first accessory data to the image-capturing apparatus.

A non-transitory storage medium storing a computer program for causing a computer to execute a control method of controlling an image-capturing apparatus to which an accessory apparatus is detachably attachable, the image-capturing apparatus providing, with the accessory apparatus, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus, the control method comprising the steps of:

• causing the image-capturing apparatus (a) to provide, by switching a signal level of the notification channel from a first level to a second level, a transmission request as the notice to the accessory apparatus to cause the accessory apparatus to transmit the accessory data to the image-capturing apparatus through the first data communication channel and (b) to transmit the camera data to the accessory apparatus through the second data communication channel,
• allowing the image-capturing apparatus to selectively perform:
• a first process to switch, after the accessory apparatus receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level;
• and
• a second process to keep, after the accessory apparatus receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level;
• and
• causing the image-capturing apparatus to, while keeping the signal level of the notification channel at the second level in the second process, receive second accessory data transmitted from the accessory apparatus as the accessory data different from the first accessory data.

A non-transitory storage medium storing a computer program for causing a computer to execute a control method of controlling an accessory apparatus detachably attachable to an image-capturing apparatus, the accessory apparatus providing, with the image-capturing apparatus, three channels that are a notification channel used for providing a notice from the image-capturing apparatus to the accessory apparatus, a first data communication channel used for transmitting accessory data from the accessory apparatus to the image-capturing apparatus, and a second data communication channel used for transmitting camera data from the image-capturing apparatus to the accessory apparatus, the control method comprising the steps of:

• causing the accessory apparatus (a) to transmit, in response to receiving from the image-capturing apparatus through the notification channel a transmission request as the notice provided by a signal level of the notification channel being switched from a first level to a second level, the accessory data to the image-capturing apparatus through the first data communication channel and (b) to receive the camera data transmitted from the image-capturing apparatus through the second data communication channel;
• and
• when the image-capturing apparatus is configured to be capable of selectively performing (a) a first process to switch, after the accessory apparatus receives the transmission request and in response thereto starts transmitting first accessary data as the accessory data, the signal level of the notification channel from the second level to the first level and (b) a second process to keep, after the accessory apparatus receives the transmission request and in response thereto ends transmitting the first accessary data, the signal level of the notification channel at the second level, causing the accessory apparatus to, while the signal level of the notification channel is kept at the second level, transmit second accessory data as the accessory data different from the first accessory data to the image-capturing apparatus.