Dumb question on OMAP-L138 EMIFA

1258021

Other Parts Discussed in Thread: OMAP-L138

Hi,

Using EMIFA interface on OMAP-L138 we have connected CPLD (uses CS2, CS4), NAND (uses CS3) and a 4-Channel UART controller (CS5).

As we are using the same data bus between them do we have to serialize the access to those peripherals in software?

If this is handled by the hardware can someone point to a technical document on this?

Thank You & Regards,

GSR

over 14 years ago

0 1258021 over 14 years ago

Genius 5120 points

Hi,

Any suggestions or comments?

Regards,

GSR

0 Bartosz Bosowiec over 14 years ago in reply to 1258021

Intellectual 750 points

Hi,

Don't know your setup and what you mean by serialization, but in general: yes, chip selects enable to share data and address bus amog various chips.

Bartosz

0 1258021 over 14 years ago in reply to Bartosz Bosowiec

Genius 5120 points

Hi,

Thank You for the reply.

When I say serialization, basically do I need to have some mutex or something so that always any one of the peripheral only is accessing the EMIFA Bus.

Regards,

GSR

0 Miguel A. Alanis over 14 years ago in reply to 1258021

TI__Genius 9490 points

GSR,

Short answer no you don't have to serialize the access.

The AEMIF controller can only access one CSx at a time and not simultaneously, so by this matter only one device will be accessed at a time from the AEMIF controller perspective and not multiple ones, so you can think of that the AEMIF controller is sort of already managing that independently as no two CS devices can be getting accessed at the same time. The other devices that are not being accessed should not be driving the databus however when they are not being accessed.

regards,

miguel

0 1258021 over 14 years ago in reply to Miguel A. Alanis

Genius 5120 points

Hi Miguel A. Alanis,

Thank you for the clarification and for the reply.

Regards,

GSR

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Dumb question on OMAP-L138 EMIFA