I'll certainly take a look at this next week.  Currently in the middle of 
finals and Maker Faire is this weekend.  And in all honesty, once i figure 
out whats going on with the driver, its still a good idea to use the kernel 
based implementation, mainly because you can take advantage of hardware 
interrupts and not have to busy wait.  I know there are sleep methods, but 
unless something like Xenomai is being used, you're at the mercy of the 
scheduler...  

Although, just to rule it out - are you still applying a device tree 
overlay?  The supplied DTS files do more than just initialize the driver, 
they setup the IO configuration, as the default board config doesn't bring 
out the eQEP lines. 

- Nathaniel Lewis

On Saturday, May 10, 2014 12:25:14 AM UTC-7, Strawson wrote:
>
> I believe it is enabled. From my last post:  the PWMSS clock config returns
> CLKCONFIG 0x111 = 000100010001
>
> According to pg 1492 of the reference manual, PWMSS_EQEP_EN is bit 4 in 
> this register which appears to be true. Furthermore the interrupt timer 
> register QUTMR 
> is incrementing away just fine. Good idea, but no dice.
>
> For good measure I will write this bit anyway, but with |= instead of = 
> since some bits are not writable and I wouldn't want to erase the enable 
> bits for pwm and ecap.
>
>
> On Friday, May 9, 2014 11:33:23 PM UTC-7, James Zapico wrote:
>>
>> Strawson,
>>
>> It looks like you're not turning the PWM EQEP clock on. There should be 
>> something to accomplish what this line from the kernel driver does:
>>
>>   // Enable the clock to the eQEP unit
>>   status = pwmss_submodule_state_change(pdev->dev.parent,PWMSS_EQEPCLK_EN
>> );
>>
>> I haven't tried this out, but it should be something like
>>  *(unsigned long*)(pwm_map_base[0]+PWMSS_CLKCONFIG) = PWMSS_EQEPCLK_EN;
>>
>> -
>> James
>>
>> On Friday, May 9, 2014 9:25:33 PM UTC-5, Strawson wrote:
>>>
>>> it seems my excitement was short-lived. While reading the position with 
>>> the previous (and attached) code does work, it only does so when Teknoman's 
>>> eqep driver is loaded. I've added writes to set up the PWMSS and eQEP 
>>> configuration registers and have confirmed by reading them back that they 
>>> are set up the same as the driver does. Any ideas on what I'm missing?
>>>
>>> // Write the decoder control settings
>>> *(unsigned short*)(pwm_map_base[0]+EQEP_OFFSET+QDECCTL) = 0;
>>> // set maximum position to two's compliment of -1, aka UINT_MAX
>>> *(unsigned long*)(pwm_map_base[0]+EQEP_OFFSET+QPOSMAX)=-1;
>>> // Enable interrupt
>>> *(uint16_t*)(pwm_map_base[0]+EQEP_OFFSET+QEINT) = UTOF;
>>> // set unit period register
>>> *(unsigned long*)(pwm_map_base[0]+EQEP_OFFSET+QUPRD)=0x5F5E100;
>>> // enable counter in control register
>>> *(unsigned short*)(pwm_map_base[0]+EQEP_OFFSET+QEPCTL) = 
>>> PHEN|IEL0|SWI|UTE|QCLM;
>>>
>>> SYSCONFIG 0xC
>>> CLKCONFIG 0x111
>>> QEPCTL0   0x9E
>>> QDECCTL0  0x0
>>> QEINT0    0x800
>>> QUPRD0    0x5F5E100
>>> QPOSMAX0  0xFFFFFFFF
>>> QEPSTS0   0xA0
>>> eqep0: -174 eqep1: 544 e^Cp2: 0
>>>
>>>
>>>

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