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Revision 3 (laforge, 02/19/2016 10:48 PM) → Revision 4/13 (laforge, 02/19/2016 10:48 PM)
This is the Analog Baseband Chip TWL3025
== USP ==
This is the SPI-like control interface between DBB and the TWL3025 (ABB).
[[Image(Iota:twl3025_usp.png)]]
== TSP ==
The CLK6.5 Signal makes things a bit more complicated than we would like. The sequence of events is something like:
* CLK_13M is applied continuously to TSL3025
* nTEN is in default state of high (inactive)
* internal CLK6.5 is in default state low
* nTEN is asserted low by TPU, some 0..65ns before CLK_13M rising edge
* next CLK13M falling edge starts first CLK6.5 rising edge
* every falling edge of CLK13M toggles CLK6.5
* TDR is sampled at every rising edge of CLK6.5 (including the first edge above)
* 7 bits are transferred during seven rising edges of CLK6.5
* TEN stays asserted for 1 CLK13M period after last bit is transferred
* TEN needs to be released before next CLK13M rising edge to prevent another transfer
[[Image(Iota:twl3025_tsp_serial.png)]]