35 lines
844 B
Markdown
35 lines
844 B
Markdown
## Rev A
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Prototype.
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### Issues
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1. **U2 - Incorrect pinout**
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* Traces to pins 5-8 should be cut
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* Connect U2-5 to MOSI (U1-17)
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* Connect U2-6 to SCK (U1-19)
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* Connect U2-7 to VBat
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* Connect U2-8 to 5V
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* **U22/U20 - Layout error**
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U20 and U22 share SER outputs with U1-4, this configuration is not usable.
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* Trace between U22-9 and U20-9 should be cut.
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* U21-10 connection to ground should be cut.
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* Connect U22-9 to U21-10.
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* **U2 - CS floating**
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CS is not pulled high and is floating when not driven by U1. May interfere with flashing U1 via ICSP.
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Connect U2-1 to 5V via 10K resistor if using ICSP.
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* **ICSP Header - Incorrect footprint used**
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Pinout not compatible with standard ICSP header.
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* **R4 & R5 - incorrect value**
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Use 270-330 Ohm instead of stated 10K. |