Difference between revisions of "SeriAlpha"
From Hackstrich
(Officially cancelling this project as SFE came out with the same thing.) |
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== Project Status == | == Project Status == | ||
| − | Revision 1 serial number 1 assembled and test code running successfully. Revision 2 designed, laid out, and sent to @laen for PCBing. | + | Revision 1 serial number 1 assembled and test code running successfully. Revision 2 designed, laid out, and sent to @laen for PCBing. PCBs and parts for rev 2 received. Project cancelled as SparkFun came out with basically the same thing. |
== Design Overview/Ideas == | == Design Overview/Ideas == | ||
| − | * Based around the ATtiny2313 in a QFN20 package | + | * Based around the <s>ATtiny2313</s> ATtiny48 in a QFN20 package |
* Individual transistors for each segment, so it will support all segments on at once and nifty things like PWMing segments | * Individual transistors for each segment, so it will support all segments on at once and nifty things like PWMing segments | ||
* Built in character generator, so you can just tell the board what letter/number to display. | * Built in character generator, so you can just tell the board what letter/number to display. | ||
| Line 18: | Line 18: | ||
== Programming Revision 1 Boards == | == Programming Revision 1 Boards == | ||
Revision 1 boards were accidentally missing a programming header. | Revision 1 boards were accidentally missing a programming header. | ||
| − | * | + | * Add a green wire from the 3rd pin down on the left I/O connector to the last resistor in the first bank under the MCU |
| − | + | * Add a green wire from the 4th pin down on the left I/O connector to the first resistor pad in the second bank under the MCU | |
| − | * | + | * This enables programming via the left connector (top to bottom): |
| − | + | ** 1 - GND | |
| + | ** 2 - GND | ||
| + | ** 3 - MISO | ||
| + | ** 4 - /RESET | ||
| + | ** 5 - MOSI | ||
| + | ** 6 - SCK | ||
| + | ** 7 - VCC | ||
| + | ** 8 - VCC | ||
| − | [[Category: | + | [[Category:Cancelled Projects]] |
Latest revision as of 13:00, 19 July 2011
SeriAlpha is a small backpack for alphanumeric LEDs (16 segment, specifically). It will accept I2C/SPI communications, and control the LED display attached to it.
Contents
Project Status
Revision 1 serial number 1 assembled and test code running successfully. Revision 2 designed, laid out, and sent to @laen for PCBing. PCBs and parts for rev 2 received. Project cancelled as SparkFun came out with basically the same thing.
Design Overview/Ideas
- Based around the
ATtiny2313ATtiny48 in a QFN20 package - Individual transistors for each segment, so it will support all segments on at once and nifty things like PWMing segments
- Built in character generator, so you can just tell the board what letter/number to display.
- Targeting the SparkFun-sold 16segment LED displays
Revision 1 Design Issues
Unable to disable RESET pin due to silicon errata, so one segment won't work.- Fixed by switching to ATmega48 in revision 2.No bypass caps on PCB- Fixed in revision 2.Board could be smaller if MCU moved to bottom of board- Fixed in revision 2.Resistor networks and dual-transistors would make assembly much easier- Fixed in revision 2.
Programming Revision 1 Boards
Revision 1 boards were accidentally missing a programming header.
- Add a green wire from the 3rd pin down on the left I/O connector to the last resistor in the first bank under the MCU
- Add a green wire from the 4th pin down on the left I/O connector to the first resistor pad in the second bank under the MCU
- This enables programming via the left connector (top to bottom):
- 1 - GND
- 2 - GND
- 3 - MISO
- 4 - /RESET
- 5 - MOSI
- 6 - SCK
- 7 - VCC
- 8 - VCC
