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Upgrade of Readout firmware

Proposal

Data are now output per TDC channel
The Trigger TDC is allways channel 0
The mapping between TDC and PETIROC is direct:
- Channel 1 of TDC $\rightarrow$ $\alpha$ Channel 0 of PETIROC
- ..
- Channel 24 of TDC $\rightarrow$ Channel 23 of PETIROC
- It allows to extend easily the number of channels and will only force to resolder adapter boards
The default clock is now 40 MHz so counts of BXID and Absolute BXID are in 25 ns. The absolute BXID is only reset at the first acquisition after Power On.

The output of a FEB now consists of:

Tag	Absolute BXID	GTC	64 or 128 channels lengths
2 bytes (B4B $)\| 6 bytes (81 days) \| 4 bytes \| 64 or 128 bytes , # channels per TDC\| It's a fixed length packet of 76 or 140 bytes. Then eache NON EMPTY TDC is sending one packet * TDC packet ^Header^ Channel^ # Channels^ payload^ \|2bytes B0B0 ^ 1 byte ^ 1bytes ^ ncx$ \times$ channel info