hi, I got problem with SPI configuration (receive only mode for ADC) using PRU, first the system setup:
during boot (ubuntu minimal) does: #SPI CLK - output, mode 3 echo 13 > /sys/kernel/debug/omap_mux/mcasp0_aclkx #D1 - input, mode 3, pulled-up echo 33 > /sys/kernel/debug/omap_mux/mcasp0_axr0 then I wrote using PRU SPI configuration (receive only mode) //enable clock for SPI1 0x44e0_0050 = 0x2 //reset spi1 0x481a_0110 = 0x2 then I wait till reset is done //module config 0x481a_0128 = 0x0 //system config - this order is recommended in datasheet 0x481a_0110 = 0x15 //configure channels - only ch0 is used, but when I don't configure 1,2,3 there's no clock on ch0 0x481a_012c = 0x7188a (d1 - input, transm on d1&d0 not used, receive only, 18-bit word, ADC SPI polarity) 0x481a_0140 = 0x6188a 0x481a_0154 = 0x6188a 0x481a_0168 = 0x6188a //enable ch0 0x481a_0134 = 0x1 //write dummy data to enable transmission 0x481a_0138 = 0x3ffff then I wait again a bit the problem is that each readback of RX register (0x481a_013c) starts the SPI clock, there's a data od D1 line but the value of RX register is always 0 -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
