EHS6 SPI configuration | Telit Cinterion IoT Developer Community
January 25, 2019 - 1:46pm, 1459 views
I have a device which one way SPI communication. Since SPI is not standard, this device has its unique way of implementing this 4-wire communication. SCK, MISO and MOSI lines are quite normal. However, the SS/CS/SSEL-line has its own way of working. CS-signal is "commonly" low active and its goes on and off for each byte that is sent or received. In our device is high active and it should stay up until 1-to-many bytes are sent to it. This is quite common deviation and it can be solved either with GPIO or makes it constantly high with resistor. Small thing even though GPIO seems to be rather slow (some milliseconds or so).
The other issue is that in SSPI configuration there are only "MSB first" and "Big Endian" configurations. Is it so that there is no way to configure the EHS6 to "LSB first" and "Little Endian" mode? In addition, there is a parameter called Chip Select mode. Are there any other choises than "One Chip Select pre Transfer Frame" (Transfer Frame = 8 bit?).
BTW, I have also the debugging challenge with Eclipse and EHS6 Concept Board (Win10). I can install and execute the MIDlet by hand with AT^SJAM. Autostart wont work, but I will deel that later. And SPI stopped working for some reason. Earlier it sent one zero (no matter what I sent) with proper SCK clock (checked with scope). Now the SPI line is mute.
Firmware version for that board is 2.0.0.0.
Hello,
If the document does not show other options there is only 'MSB first' and 'Big Endian' possible. It's the same about 'One Chip Select per Transfer Frame.' These parameters, where only one option is possible, may be available for compatibility reasons.
Please check "GPIO/mode/SPI" in AT^SCFG? output.
Regards,
Bartłomiej