Custom Calypso Board¶
This wiki page is about some old/obsolete thoughts on the merits of creating a custom TI calypso board.
The rationale is quite simple: The supply of Motorola/Compal phones is limited, and the quality that's available
at this point often is some quite extensively repaired (not just refurbished) phones.
As the TI Calypso/Iota/Rita chipset is still available in quantity from the grey market, we can simply build our
own board from it.
We have an existing Ti Calypso design similar to that used in the Compal/Motorola phones.
It does not have an interface for LCM or Keypad.
- expose JTAG on a standard header
- board-edge connector for plugging many boards into one backplane
- external clock input / buffered clock output
- RF connector standard u.fl or SMA or optionally separate Rx/Tx on the back-plane
- I2C/SPI and both UARTs available on headers
- on-board EEPROM for storing persistent data, even beyond NOR flashing
- SIM card slot, SIM interface also present on header
- additional / unused TPU ports
- header for TSP / TPU and all data/control interfaces between iota/rita/calypso
- RTC crystal and footprint for backup battery
- version of the board with uplink / downlink filters switched