Work Update

Last week I worked on and am almost finished with the chip detection driver. This was something of a departure from the RFID driver because it was a whole new piece of hardware, and it was built on an I2C driver rather than an SPI driver. Luckily, the INA219 did not require nearly as much setup or configuration as the MFRC522 did.

One hiccup I ran into was that the resistor built into the INA219 was too small to measure the current in the circuit directly. I ended up using another resistor in series with the set of chip resistors in parallel and measuring the potential difference across it, which was large enough to not be a problem for the INA219. Another potential problem is that the accuracy of the INA219 is good, but not perfect. However, I think that by looking at the change in chip value rather than the absolute value at any time we can make some assumptions about what the correct set of values is.

Schedule Update

I believe I’m still on track for my tasks. Next week I will work on the driver for the e-ink screen, which will make the play area subsystem more or less complete software-wise.