synchronous 16 bits muxed EIM communication

[tristanlelong]

Hello,

I am trying to communicate the with a SRAM chip over the EIM bus on an i.MX6.

It uses the following signals:

CS0

OE

RW

LBA

EB0/EB1

ADDR/DATA[0-15]

It doesn't have the WAIT pin connected and uses a external chip to latch addresses.

I configured the EIM_CS0GCR1, EIM_CS0GCR2, EIM_CS0RCR1, EIM_CS0RCR2, EIM_CS0WCR1, EIM_CS0WCR2 but I might still be confused with timings: what are their references and how they are related to each other.

I then tried to access the SRAM by doing read and write on the address range [0x08000000 - 0x08004000] which should be 16KB on the CS0. But only get strange values. Writing is not working either.

My configuration:

EIM_CS0GCR1: 0x07f1003f

EIM_CS0GCR2: 0x00001002

EIM_CS0RCR1: 0x08785000

EIM_CS0RCR2: 0x00000028

EIM_CS0WCR1: 0x88e28800

EIM_CS0WCR2: 0x00000000

I tried google but it seems that only asynchronous mode is used by other people.

Any idea on what I am doing wrong: wrong configuration? missing step?

Thanks

Regards

[tristanlelong · Accepted solution]

Actually I found the correct timings, and it is now working:

For reference, the working configuration is:

EIM_CS0GCR1: 0x07f1303f

EIM_CS0GCR2: 0x00001001

EIM_CS0RCR1: 0x08386000

EIM_CS0RCR2: 0x00000068

EIM_CS0WCR1: 0x88630c00

EIM_CS0WCR2: 0x00000000