tetris/readme.md

## Debugging

```
mspdebug rf2500 gdb

msp430-gdb -x firmware.gdb
```

Attention: the gdb in the TI toolchain package is broken, use the one from Debian



## Signals Working Cycler

These signals are related to code under tag `cycler_works_include_output_stage`.

First octets:

![](./docs/cycler_working_first_octets.png)

Last octets:

![](./docs/cycler_working_last_octets.png)

Schematics and legend for signals:

![](./docs/schematics.jpeg)


## Timing

Complete cycle: 2.48us

![](./docs/pulse_complete.png)

Short pulse: 550ns

![](./docs/pulse_short.png)

Long pulse: 1.18us

![](./docs/pulse_long.png)


## Load Time

During of loading data into five LEDs: 297us

![](./docs/five_leds.png)

During of loading data into six LEDs: 297us

![](./docs/six_leds.png)


| # of LEDs | Load Time measured | calculated |
| --------- | ------------------ | ---------- |
| 5         | 297us              |            | 
| 6         | 354us              | 356.4us    |
| 10        |                    | 594us      |
| 100       |                    | 5.9ms      |
| 200       |                    | 11.8ms     |


## Reset Circuitry

It appears that the output voltage of the power supply raises that slow, that the MCU
will not handle the reset correctly.

The following circuitry should generate a valid reset signal far enough from the raise 
of the supply voltage:

![](./docs/reset-circuit.jpeg)

The circuit generates the following signals:

![](./docs/reset-signal.png)

Yellow is the supply voltage, green is the voltage at the inverting input of the opamp
(reference voltage), purple is the voltage at the non-inverting input of the opamp at the RC element
and blue finally is the reset signal. Lets hope that the small peak when switching on power
won't hurt.