I'm just getting started interfacing to the TLC1518 over SPI from a PIC32 uC. (SPI is configured for 16 bit mode)
The data sheet is either lacking, or I am interpreting it incorrectly. Here are the issues I have:
I write the required 0xA000 first and then clear out the SPI input buffer
I write my CFR config (0xA004) to the device and then clear out the SPI input buffer.
When I read the CFR I always get 0xX084. The extra bit is the INPUT SEL bit. I set it to NORMAL (0) but it comes back as PSEUDO DIFFERENTIAL (1). I verified w/a scope both the write and read and can see I sent a 0 in that bit position and that the 1518 sent a 1 back. Any idea why this is happening.
I then moved on to try a one shot conversion. I am setup for a NORMAL conversion (Not extended....although I can't find in the data sheet how you select this option). I am using the SCLK w/CS to perform the conversion. I issue the 0x0000 command to perform a conversion on channel 0 and clear the SPI input buffer. I see the EOC line go low at the end of the string of SCLKs, but it never goes back high. The data sheet seems to imply it will go high when the CS goes high, but it does not. What will cause it go to back to the high state? I issue another 0x0000 command to try and read the converted data, but all I ever get is 0xFFF0 regardless of the voltage I apply to the input pin A0.
What am I missing (other than the data :-)?
Thanks,
Joe B.