Image forming apparatus, startup control method, and non-transitory computer-readable recording medium encoded with startup control program

1. An image forming apparatus comprising:

a main processor set as a root complex of PCI Express;

a startup processor configured to control startup of the main processor; and

a connection portion connectable with an option board having a sub processor set as a root complex of PCI Express,

the startup processor further configured to: control portion including

detect that an option board having a sub processor set as a root complex of PCI Express is connected to the connection portion,

acquire ability information about the option board at a stage before the main processor starts up, when the option board is detected,

select one of the main processor and the sub processor, based on the acquired ability information, and

start as a root complex the main processor when the main processor is selected, and start as a root complex the sub processor when the sub processor is selected.

2. The image forming apparatus according to claim 1 , wherein the startup processor is further configured to start the main processor without starting the sub processor when the main processor is selected, and to start the sub processor after setting the sub processor as a root complex without starting the main processor when the sub processor is selected.

3. The image forming apparatus according to claim 1 , wherein when the option board includes a sub image processor configured to process an image, the startup processor is further configured to set and start the sub image processor as an end point even when one of the main processor and the sub processor is selected.

4. The image forming apparatus according to claim 3 , when the option board does not include a sub image processor having a circuit for processing an image, the startup processor includes a cut-off portion to cut off power to be supplied to the option board when the main processor is selected.

5. The image forming apparatus according to claim 1 , wherein the startup processor is further configured

to compare a processing speed of the sub processor defined by the ability information with a processing speed of the main processor, and

to select one of the sub processor and the main processor that has a higher processing speed.

6. The image forming apparatus according to claim 5 , wherein when the main processor is selected by the startup processor, the startup processor is further configured to select the sub processor when the ability information indicates that a program processing portion that processes an image by executing a predetermined program is mounted on the option board.

7. The image forming apparatus according to claim 6 , wherein when the sub processor is selected by the startup processor, the startup processor is further configured to start the main processor after setting the main processor as an end point and to start the sub processor after setting the sub processor as a root complex.

8. The image forming apparatus according to claim 7 , wherein

a program storage portion that stores a startup program for allowing the main processor to perform a predetermined process is mounted on the option board, and

the startup processor is further configured to allow the main processor to execute the startup program stored in the program storage portion to start up.

9. The image forming apparatus according to claim 1 , further comprising a main image processor mounted on a same board as the main processor and having a circuit for processing an image, wherein

the startup processor is further configured to start the main image processor even when one of the main processor and the sub processor is selected.

10. A startup control method performed in an image forming apparatus,

the image forming apparatus including

a main processor set as a root complex of PCI Express, and

a connection portion connectable with an option board having a sub processor set as a root complex of PCI Express,

the method allowing the image forming apparatus to perform:

a detection step of detecting the option board connected to the connection portion;

an acquisition step of acquiring ability information about the option board at a stage before the main processor starts up, when the option board is detected;

a selection step of selecting one of the main processor and the sub processor, based on the acquired ability information; and

a switch step of starting the main processor as a root complex when the main processor is selected, and starting the sub processor as a root complex when the main processor is selected.

11. The startup control method according to claim 10 , wherein the switch step includes a selection startup step of starting the main processor without starting the sub processor when the main processor is selected, and starting the sub processor after setting the sub processor as a root complex without starting the main processor when the sub processor is selected.

12. The startup control method according to claim 11 , wherein

the selection step includes

a speed comparison step of comparing a processing speed of the sub processor defined by the ability information with a processing speed of the main processor, and

a speed basis selection step of selecting one of the sub processor and the main processor that has a higher processing speed.

13. The startup control method according to claim 12 , wherein when the main processor is selected in the speed basis selection step, the selection step includes a particular condition selection step of selecting the sub processor when the ability information indicates that a program processor that processes an image by executing a predetermined program is mounted on the option board.

14. The startup control method according to claim 13 , wherein when the sub processor is selected in the particular condition selection step, the switch step includes an overlap startup step of starting the main processor after setting the main processor as an end point, and starting the sub processor after setting the sub processor as a root complex.

15. The startup control method according to claim 14 , wherein

a program storage portion that stores a startup program for allowing the main processor to perform a predetermined process is mounted on the option board, and

the overlap startup step includes a particular condition startup step of allowing the main processor to execute the startup program stored in the program storage portion to start up.

16. The startup control method according to claim 10 , wherein when the option board includes a sub image processor having a circuit for processing an image, the method allows the image forming apparatus to further perform a sub image processing startup step of setting and starting the sub image processor as an end point even when one of the main processor and the sub processor is selected.

17. The startup control method according to claim 16 , wherein when the option board does not include a sub image processor having a circuit for processing an image, the method allows the image forming apparatus to further perform a cut-off step of cutting off power to be supplied to the option board when the main processor is selected.

18. The startup control method according to claim 10 , wherein

the image forming apparatus further includes a main image processor mounted on a same board as the main processor and having a circuit for processing an image, and

the method allows the image forming apparatus to further perform a main image processing startup step of starting the main image processor even when one of the main processor and the sub processor is selected.

19. A non-transitory computer-readable recording medium encoded with a startup control program executed in a computer controlling startup of an image forming apparatus,

the image forming apparatus including

a main processing portion set as a root complex of PCI Express, and

a connection portion connectable with an option board having a sub processing portion set as a root complex of PCI Express,

the program causing the computer to perform:

a detection step of detecting the option board connected to the connection portion;

an acquisition step of acquiring ability information about the option board at a stage before the main processing portion starts up, when the option board is detected;

a selection step of selecting one of the main processing portion and the sub processing portion, based on the acquired ability information; and

a switch step of starting one selected from the main processing portion and the sub processing portion as a root complex.

20. The non-transitory computer-readable recording medium encoded with a startup control program executed in a computer controlling startup of an image forming apparatus according to claim 19 , wherein the switch step of starts the main processor as a root complex when the main processor is selected, and starts the sub processor as a root complex when the main processor is selected.