Dear E2E:
Thank you for your help.
I use McASP on OMAP-L138 to receive 144 bits of data from ADC converter - AD7608.
ADC converter has 8 18-bit channels - the total number of bits on serial interface is 8*18=144bits.
1. I will configure McASP for 9 slots of 16 bits (9*16=144) because 18 bits slot is not supported.
2. How the received data will look in the receive FIFO which is 32-bit wide?
3. I assume - the eight (7:0) 18-bits words will be packed in five (5) 32-bit words as: W7_bit[17:2], W7_bit[1:0],W6[17:4] (first 2x16-bit or 32-bit).
W6_bit[3:0],W5_bit[17:6],W5_bit[5:0],W4_bit[17:8] (second 2x16 bit or 32-bit) etc... The last 32-bit word will look as: W0_bit[15:0],Next 144-bit stream (9x16-bit words).
Is this correct? Or each 16-bit slot will be written to the separate FIFO address?
4. SW will need to "unpack" the received bit stream in order to get 18-bits readings for each ADC channel.Is it correct?
5. Is there a better way to receive eight (8) 18-bit readings (or 144-bit bit stream) to McASP on OMAP-L138?
Thank you for your help,
Boris Ruvinsky