Difference between revisions of "Project Peacock"
From Hackstrich
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* Display Controller MCU | * Display Controller MCU | ||
** Communicate with host via I2C/SPI/RS232 | ** Communicate with host via I2C/SPI/RS232 | ||
+ | ** Will need a lot of I/O pins | ||
+ | *** RAM address bus - 22 pins | ||
+ | *** RAM data bus - 16 pins | ||
+ | *** RAM arbitration/handshaking - 6 pins | ||
+ | *** SPI/I2C/RS232 - 4 pins | ||
+ | *** '''Rough total - 48 I/O pins required''' | ||
* Display Driver CPLD | * Display Driver CPLD | ||
** Essentially just the digital part of a RAMDAC, constantly reads data from the RAM and spits it out to the output converter | ** Essentially just the digital part of a RAMDAC, constantly reads data from the RAM and spits it out to the output converter | ||
+ | ** Since it's dealing with RAM anyway, it can handle the RAM details for the MCU (accept raw data from the MCU and write it to memory) | ||
** Using a CPLD means the Display Controller MCU doesn't need to be super-fast | ** Using a CPLD means the Display Controller MCU doesn't need to be super-fast | ||
* RAM | * RAM |
Revision as of 01:39, 11 September 2010
Project Peacock will be (in theory) a chipset for doing DVI/VGA display output from a microcontroller. It will consist of:
- Display Controller MCU
- Communicate with host via I2C/SPI/RS232
- Will need a lot of I/O pins
- RAM address bus - 22 pins
- RAM data bus - 16 pins
- RAM arbitration/handshaking - 6 pins
- SPI/I2C/RS232 - 4 pins
- Rough total - 48 I/O pins required
- Display Driver CPLD
- Essentially just the digital part of a RAMDAC, constantly reads data from the RAM and spits it out to the output converter
- Since it's dealing with RAM anyway, it can handle the RAM details for the MCU (accept raw data from the MCU and write it to memory)
- Using a CPLD means the Display Controller MCU doesn't need to be super-fast
- RAM
- SRAM
- Far too expensive (~$200) for the amount needed
- PSRAM (Pseudo SRAM)/CellularRAM
- SRAM interface but DRAM backend, simple to interface with and cheap (~$6)
- Only available in VFBGA package meaning a four-layer board would be required, and hard to solder
- SDRAM
- Inexpensive (~$5) and readily available
- Easy non-BGA SMT packages
- Harder to interface with, would need to have the CPLD handle RAM refreshing and other housekeeping
- SRAM
- Output converter
- TMDS converter for DVI
- DAC for VGA