IF2C: Quick Start

Posted byOBAdmin

The IF2C and GXN board-pair package has shipped with updated firmware on the GXN to handle the command set on the IF2C. Your UT software would need to be updated to speak these extra commands. In the meantime, you can use a serial port program to send those few extra commands first (as needed) and then switch over to your UT software.

Materials (Get Stuff Ready)

  1. Battery: Single-cell Lithium-ion polymer with JST-PH connector: See this Digikey search.
    1. “Wait, I don’t like those JST-PHs…” sure, yep, you can populate the screw terminal block component with this TE 282834-2 Part or the general purpose 1×2 0.100″ male header or of course solder wires to your favorite in-line etc.
    2. Watch for the little “+”s on the PCB in silkscreen (do they really use silk anymore?). The polarity of the JST-PH should match generally prototyping style JST implementations of battery polarity.
  2. Jumper wire to bring +5VDC from the IF2C to the HOST. Perhaps included in your shipment. Perhaps you want to rework this and wire it to your liking.
  3. USB cable ending in a Mini-B for charging only (not data at this point).
  4. HOST board with comms module of choice, configured to your taste and needs.
  5. SMA-SMA cables, at least 2, short ones – these are just board-to-board jumpers. Shorter cable = less inductance etc.
  6. Transducers with SMA cable terminations, at least one.
  7. Maybe an SMA-MMCX cable so you can test the MMCX connector(s) on the IF2C.
  8. Maybe your favorite serial port terminal program (CoolTerm, HyperTerm, whatever it is) so you can issue commands directly, if the UT software has not yet been updated to handle the IF2C commands.

Steps to Assemble and Power Up

  1. Choose your HOST board (here, if referenced, the host is a DL0102GXN)
  2. Know what your HOST board configuration and firmware status is.
    1. See IF2C/Host comms options
    2. For example: are you using a socketed radio (XBee (TM?) style) that controls the HOST main power with a GPIO pin? Is the jumper set correctly?
    3. Are you using firmware that has been updated to work with the IF2C command set?
    4. Here, we assume you’re using the firmware that shipped on a demo GXN board that integrates the API for the IF2C. But that your UT software doesn’t yet supported the automated use of the same API.
  3. STACK! The IF2C can be stacked on top or underneath the HOST board. They both work. However, so far at the bench here, stacking with the IF2C on the bottom gives better noise performance when hosted by a DL0102G(XN) due to various switchers etc. on the HOST that create some (electro)magnetic storms under the IF2C.
    1. Use standoffs/spacers. The spacing is slightly greater with the HOST on top.
    2. The GPIO 2×12 header is what stacks. You’ll see the 3x screw mount holes line up too. One is Southwest (SW) and the other is Southeast (SE) and the 3rd is oddly placed in the Northish area under in the radio/multi-comms footprint.
    3. The flip side to the stacking order is that the GXN (R01 A1) as a HOST can only be programmed via its TAG-CONNECT interface when it is separate or stacked on the bottom. By design.
  4. Connect the IF2C power to the HOST:
    1. The +5VDC from the IF2C goes to the +VSYSIN terminal on the HOST. Ground is already connected at a single point via the GPIO stacking header.

Steps to Connect Signals and Transducers

  1. Connect the HOST channel for Tx to the XPULSE_IN connector which is on the NW corner of the board, a vertically-oriented surface mount SMA connector, left-most. If your host is the DL0102GXN, use Chan 1 as the Tx signal (this is your only option).
  2. Connect the HOST channel for Rx from the IF2C (Chan 2 on the GXN) to XRX_OUT_BUF (South-central) on the IF2C. You could alternately try connecting to the XFX_OUT (non-buffered output). These are the right-angle (R/A) through-hole (TH) SMAs on the board. Be careful not to zap components under the SMA barrel area.
  3. Connect your transducer(s) to whatever channel(s) you want to on the IF2C. Four channels, starting with Chan 1 at the top (North) centerish, are numbered in increasing channel number moving Westward. Chans 1 – 4 are the surface mount (SMD) SMA straight connectors. Chans 5-8 are numbered in increasing order going from North to South along the West edge of the board. These are the edge-launch SMAs.

Steps to Power Up and Talk to the Board(s)

  1. Power Up! Plug in the battery (to the board, not to an AC outlet or something like that). That just turned things on. Assuming the battery was reasonably charged.
  2. Have your USB-Mini-B cable handy for charging. Maybe plug that in. A standard USB port is fine. As shipped, the charge current is limited acceptably for use by a standard USB port.
  3. Use your UT software to check that you can talk to the HOST, and/or that your comms module is configured correctly, etc. Or use a serial terminal program (again, maybe CoolTerm? that’s what’s used here) to send some commands.
    1. WAIT! First command didn’t work? The default firmware that ships on the HOST GXN now contains a sleep command with a 1-minute timeout from active operation (comms) until sleep. So, just send the command twice. Your UT software probably needs to be updated to work with a sleeping HOST.
  4. With updated firmware, the HOST receives all commands and forwards IF2C commands as needed.

Example data acquisition sequence, step by step.