AM2432: GPMC 32-bit Data

Mari Tsunoda

Part Number: AM2432
Other Parts Discussed in Thread: SYSCONFIG

Hi Team,

My customer is currently considering the AM243x, but they have a question about the GPMC.

I see that in the TRM, it shows examples of multiplexing the address and data bus for 32-bit data width. Is it possible for 32-bitt data transmission without multiplexing?

Best regards,

Mari Tsunoda

over 3 years ago

0 Ming Wei over 3 years ago

TI__Guru 55945 points

Hi Mari,

According to the AM243x TRM, the only two non-multiplexed data transmission GPMC supported are:

16-Bit Non-Multiplexed and

8-Bit Non-Multiplexed

For 32 bit data transmission, it has to be 32-Bit Address/Data-Multiplexed.

See 12.3.3.2.1 GPMC Modes in TRM for details.

Best regards,

Ming

0 Mari Tsunoda over 3 years ago in reply to Ming Wei

TI__Expert 5726 points

Thanks Ming.

Best,

Mari

0 Mari Tsunoda over 3 years ago in reply to Ming Wei

TI__Expert 5726 points

Hi Ming,

I saw this other thread regarding non-muxed 32-bit: https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1004809/am6442-about-general-purpose-memory-controller-gpmc/3717960#3717960

Looking at this thread, I'm assuming it would apply to the AM243x as well, so does this mean that since it only has 21 address bits, it would have 2^21*4Bytes=8MB per CS and 32MB in total (as there is up to 4 CS)?

Best regards,

Mari Tsunoda

0 Ming Wei over 3 years ago in reply to Mari Tsunoda

TI__Guru 55945 points

Hi Mari,

You are correct. According to the Table 12-3356 shows the use of address and data GPMC pins based on the type of external device in TRM, there are 23 address pins you can used for address and leave the 32 A/D pins for data in non-multiplex mode.

As of the addressable space size for GPMC, the largest addressable space for 32 bit data non multiplexed mode is 2^23 which is 8MB, for 4 CS you can get up to 32MB.

Best regards,

Ming

0 Mari Tsunoda over 3 years ago in reply to Ming Wei

TI__Expert 5726 points

Hi Ming,

Thanks for confirming. Can you also tell me how to configure settings for 32-bit non-mux data in SysConfig?

Best,

Mari

0 Mari Tsunoda over 3 years ago in reply to Ming Wei

TI__Expert 5726 points

Hi Ming,

Any updates on the sysconfig setting information?

Best,

Mari

+1 Ming Wei over 3 years ago in reply to Mari Tsunoda

TI__Guru 55945 points

Hi Mari,

Since GPMC is not currently supported in the MCU+ SDK, the SysConfig does not support GPMC. If you want to use the GPMC for your application, you will have to access the GPMC registers directly.

Best regards,

Ming

0 Mari Tsunoda over 3 years ago in reply to Ming Wei

TI__Expert 5726 points

Hi Ming,

Thanks. I see that they can configure everything in the GPMC_CONFIG registers.

Best,

Mari

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AM2432: GPMC 32-bit Data