currently we are migrating from 214xx DSPs to new SHARC+ DSPs. If someone is able to clear the following questions regarding the SPI slave boot mode this would be great.
- The ADSP-214xx uses a special boot kernel (the first 384 words of an ldr file created with elfloader). Am I right that the SHARC+ DSPs are using an internally stored boot kernel and we only need to pack and transmit our application converted with elfloader without any additional boot kernel?
- The HRM of the 215xx mentions the usage of a SPICMD as first byte of the boot stream to configure the SPI mode of the slave. Is this byte automatically added by the elfloader if calling it with the configuration spislave mode or should it be added manually?
- The HRM also mentions that the data has to be sent as multiplies of 1024. In our case the last package will consists of ~300 bytes - should we add padding bytes for the last package? If yes zero seems to be a good value
- Is it necessary to parse the ldr file created by elfloader (with the binary option enabled) or is it possible to simply send this file via SPI to the DSP?
- Am I right that the SPI format hasn't been changed between the SHARC and the SHARC+ DSPs except for the byte (SHARC+) vs. word transmission (SHARC)?
I have answered the questions for my self.
- The SPICMD has to be added manually
- Padding in the last package doesn't seems to be necessary
- Parsing of the ldr in binary mode is not necessary
- The SPI format has changed (clock polarity)
Another forum entry mentioned that the bit format is "could be" LSB - I am using MSB as before and this seems to be the right format.