Dm3730 8 bit memory access

ilker kaya

Other Parts Discussed in Thread: DM3730

Hi,

Cs0 of Dm3730 is connected to nor-flash by configuring 16-Bit Address/Data Muxed mode and cs4 of dm3730 is connected to one device that has 8-bit data and 5-bit Address. How will we connect to A0 pin of this device to Dm3730 ?
Thanks

İlker KAYA

over 9 years ago

0 Cvetolin Shulev-XID over 9 years ago

TI__Guru 65405 points

Hi İlker,

Refer to AM/DM37x Multimedia Device Technical Reference Manual Figure 10-37. GPMC Connection to an External NOR Flash Memory.
www.ti.com/.../technicaldocuments
Check also memory pin multiplexing and Table 10-24. describing supported memory interfaces and their connections to GPMC.

BR
Tsvetolin Shulev

0 ilker kaya over 9 years ago in reply to Cvetolin Shulev-XID

Intellectual 370 points

Hi,

Thanks for your reply.

There is no connection for 8-Bit Address/Data Muxed pSRAM or NOR Flash. Does Dm3730 support 8-Bit Address/Data Muxed mode?

Thanks.

0 Cvetolin Shulev-XID over 9 years ago in reply to ilker kaya

TI__Guru 65405 points

İlker,

There is a limitation about booting from 8-bit pSRAM or NOR Flash because:
The bootdevicesize input pin (GPMC boundary) defines the size of the attached device on chipselect 0 and is used to configure the GPMC.GPMC_CONFIG1_i[13:12] DEVICESIZE bits (where i = 0). A BOOT_DEVICE_SIZE signal is propagated from the SCM. Its value is fixed at 0x1 at IC reset, causing a 16-bit wide external memory to be used.

BR
Tsvetolin Shulev

0 ilker kaya over 9 years ago in reply to Cvetolin Shulev-XID

Intellectual 370 points

Thanks for your reply.

After booting, If we access one component that has 8 bit datas and addresses by configuring CS4 for “8-Bit Address/Data Muxed mode” or “8-Bit Address/Data non-Muxed mode”, Can we get the address_0 value ? in other word, How will we connect to A0 pin of this device to Dm3730 ?

ilker

0 Cvetolin Shulev-XID over 9 years ago in reply to ilker kaya

TI__Guru 65405 points

The external device memory A[0] should be connected to GPMC A[1] see the Note above Figure 10-3.

BR
Tsvetolin Shulev

0 ilker kaya over 9 years ago in reply to Cvetolin Shulev-XID

Intellectual 370 points

Thanks

0 ilker kaya over 9 years ago in reply to ilker kaya

Intellectual 370 points

Hi,

I tried the access. When the access is done, the related address pins of DM3730 is measured by scope. The address pins are changed like below but there is no value of zeroth bit.

DM3730 DM3730_Pin

Address A5A4A3A2A1
0x00 00000
0X01 00000
0X02 00001
0X03 00001
0X04 00010
0X05 00010
0X06 00011

0 Cvetolin Shulev-XID over 9 years ago in reply to ilker kaya

TI__Guru 65405 points

Ilker,

The memory address lines are shifted by 1 because the device does not provide the A0 byte address line required for random-byte addressable 8-bit-wide device interfacing (for multiplexed and non-multiplexed protocol). This could causes confusion. Address line A1 should be connected to gpmc_d[0] pin as it is shown at figure 10-2.
An other specific setting when using 8-bit data device is to set the GPMC.GPMC_CONFIG1_i[13:12] DEVICESIZE bit field to 0x0.

BR
Tsvetolin Shulev

0 ilker kaya over 9 years ago in reply to Cvetolin Shulev-XID

Intellectual 370 points

Thanks for your comments.

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Dm3730 8 bit memory access