From fa54bc1dd5d6b2190f53e3d011869a35b2cf3697 Mon Sep 17 00:00:00 2001 From: Jan Michel Date: Tue, 14 Jul 2015 17:44:12 +0200 Subject: [PATCH] updated SPI interface description --- trb3/DacProgramming.tex | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/trb3/DacProgramming.tex b/trb3/DacProgramming.tex index 318f29f..c22c8d5 100644 --- a/trb3/DacProgramming.tex +++ b/trb3/DacProgramming.tex @@ -60,6 +60,21 @@ The ASCII format is shown below, the commands can be found in table~\ref{ltc2600 \item Example Configuration: daqtools/config/DAC\_config.db \end{itemize*} +\paragraph*{Registers}~\\ + +\begin{tabular}{c|c|l} + 0xd40N & Data & 16 places for SPI commands \\ + 0xd410 & Chip Select & CS output, one bit for each of the 15 outputs, positive logic\\ + 0xd411 & Control & Control register. See next paragraph\\ + 0xd412 & Readback & Data received on SPI\\ + 0xd413 & Master & Block SPI for other use. See next paragraph\\ + 0xd414 & Clear & Additional output to connect to a CLR-input on SPI devices\\ + 0xd418 & Invert & Set lowest bit to invert all outputs\\ + 0xd419 & Word Length & Number of bits of a SPI word, default: 32\\ + 0xd41a & Period & Half period of a SPI clock cycle, in system clocks. default: 7\\ + +\end{tabular} + \paragraph*{Collisions during reading} Writing to all registers is blocked while a transfer is in progress, i.e. writing can not be broken. Reading back a value can break, if to processes access the SPI port in a interleaved manner, because reading the read-back register is non-atomic. -- 2.43.0