wiki:TTTT Users Manual

Connecting to TTTT via usb serial

  • The TTTT uses a FTDI USB to serial chip, so if it is plugged in to a linux computer, it should create a device in /dev called ttyUSBX where X is 0 - N
  • This can be opened with minicom with the no hardware flow control and 115200 baud 8N1.


  • help: list commands
  • rw: register write
    ex: ">rw 31 0DEB0000000000F1" writes 0x0DEB0000000000F1 to register 0x31
    Full Register map (You may have to download the PDF for it to work)
  • rr: register read
    ex: ">rw 31" reads the contents of register 0x31
  • bmesg
  • l1a_rng: BX range that L1As are allowed to be sent out.
    ex: ">l1a_rng 100 D00" allows triggers on BXings greater than or equal to 0x100 and less than 0xD00
  • l1a_en: enabled trigger sources (look at register 0x35)
    ex: ">l1a_en 1" enables the periodic trigger but doesn't change the state of the other trigger sources

1 - periodic
2 - random
4 - external

  • l1a_dis: disable a trigger source
    ex: ">l1a_dis 2" disables the random trigger but doesn't change the state of the other trigger sources
  • l1a_per: set the 16-bit period parameter (larger means lower rate)
  • l1a_rand: set the 16-bit random parameter (larger means lower rate)
  • set_rules: sets which trigger rules are active
  • get_rules: prints the current trigger rules 0F means all rules are enforced, 0x1 means only
  • l1a_adv: used to send a broadcast message and an l1a at specified bunch crossings in one orbit
    ex: ">l1a_adv c00 d00 80" sends an l1a at BX 0xc00 and the boardcast message 0x80 @ bx 0xd00
  • l1a: send 1 L1a at the next BX that is in the l1a range (set by l1a_rng)

Other features

  • bit 1 of register 0x31 enables the use of the TTS state to control sending L1As. (I'll add a command later)
  • bit 0 of register 0x00 resets all registers to their power-up state.


Periodic trigger mode

Before doing the following commands, make sure the trigger rules are set the way you want and bit 1 of reg 0x31 is set to use/not use TTS state.
Also, you may want to set/check the range of allowed L1A BXs in register 0x31

Disable trigger sources
>l1a_dis 7
Set period parameter for the periodic trigger (this gives about 600hz on the AMC13)
>l1a_per FFFF
Enable the periodic trigger generator
>l1a_en 1

Last modified 7 years ago Last modified on Nov 2, 2015, 11:43:26 AM