Logic Analyzer Connections for Reverse Engineering
| Signal | EPD pin | CC1110 pin | Logic Analyzer pin | Notes |
|---|---|---|---|---|
| GND | 18 | - | 1 | |
| MOSI | 14 | 34 | 2 | |
| CLK | 13 | 36 | 3 | |
| nReset | 10 | 1 | 4 | Optional |
| nCS | 12 | 3 | 5 | |
| Busy | 9 | 4 | 6 | |
| D/nC | 11 | 13 | 7 | |
| nEnable | x | 12 | 8 | Optional |
| nCS1 | 1 | 7 | 9 | Only Needed on some models with dual EPD controllers (Chroma42) |
The logic analyzer can be connected to the tag either by soldering tiny wires to the PCB.
It seems easier to solder wires to the SOCs pins than to the EPD cable's connection point.
The logic analyzer can also be connected to the tag by using a "Spider board" to probe the connections.
Probing the EPD cable's connection point with a spider board is possible but difficult, the next time I'll try probing the SOC pins instead.
Note: PCBs from other manufactures often use a connector for the EPD, these are MUCH easier to probe since the connector has a small ridge of plastic between the pins which aids the alignment.
Eventually I removed the EPD from a Chroma29 controller and replaced it with a 24 pin FFC connector.
This plus a breakout board fabricated from two 24 pin FFC to .1 inch ribbon cable adapters provided the easiest way to connect a logic anaylzer found to date.
| Signal | SPI Flash pin | Logic Analyzer pin |
|---|---|---|
| Gnd | 4 | 1 |
| CS# | 1 | 2 |
| MISO | 2 | 3 |
| MOSI | 5 | 4 |
| SCLK | 6 | 5 |