Someone could please help me to setup the SMC timers?

www.nxp.com/documents/data_sheet/SC16C2550B.pdf

The master clock is 133 MHz (i.e. 7.5 ns cycles)

I'm trying with that:

static struct sam9_smc_config tms_uart_smc_config = {
.ncs_read_setup = 0,
.nrd_setup = 2,
.ncs_write_setup = 0,
.nwe_setup = 2,

.ncs_read_pulse = 8,
.nrd_pulse = 4,
.ncs_write_pulse = 5,
.nwe_pulse = 3,

.read_cycle = 8,
.write_cycle = 6,

.mode = AT91_SMC_READMODE | AT91_SMC_WRITEMODE | AT91_SMC_EXNWMODE_DISABLE | AT91_SMC_DBW_8 | AT91_SMC_BAT_WRITE,
.tdf_cycles = 4,
};

Thanks in advance
BR
Edgard

Hello,

It's always complicated and/or boring to find these timings!

You don't give us the Vcc value then I will only give you the timing not the number of clock cycles.

I am using name from the atmel datasheet. I don't give you all the values, you cand find them by yourself with the diagrams.

NRD_PULSE = t7w
NCS_RD_SETUP = t6s
NRD_SETUP = t7d
NRD_HOLD is used to respect t9d constraint so I will put 10ns

NWE_PULSE = t13w
NCS_WR_SETUP = t6s
NWE_SETUP = t13w
NWE_HOLD = t16h because of t15d

I don't really know for TDF_CYCLES probably t12h

Concerning the modes I don't know if all settings are ok since I don't have the schematic of your board.

Don't hesitate to increase timings and to reduce them when it's ok. I have encountered some troubles with timing really close to the minimun. It was ok outside Linux with sam-ba for example but I had read errors at linux boot time.

Regards

Ludovic

Hi Odulo,

Thanks for your reply. Unfortunately still not working.

I'm working with 3.3V

I did as you said, just did
NWE_SETUP = t13d (I think you mistyped t13w)
and then NWE_HOLD = 15 ns because of t15d

But it still doesn't work.

I really don't know where look for.
I have urgency to solve this. Could you remote work with me? Or point some1 able to to remotely help me?

I have o lot of things working fine with my at91sam9g45-ekes based board...And I just need to make this ext serial and a ext sram to work.

We are willing to pay for the consulting.

Best Regards.

Hi Elima,

Sorry it didn't help you. I don't really know where you can find help, maybe your uart vendor. But are you sure that your problem comes from timings?
I mean I had troubles one time to configure smc for a nand devices but it was not only timings. I don't know if this information can help you but the mtd driver accessing to the nand was doing 8-bits accesses instead of 16-bits accesses. It may not be a problem, the smc may manage this but I don't know why it was not working.

Regards

Ludovic