Recovery Boot

A recovery boot is a multi-step boot operation:

1. module is off and connected;
2. EEPROM switch is set in a way to disable EPPROM connection to USB FX2 microcontroler;
3. module is powered on;
4. module enumerates in recovery mode (VID = 0x04B4, PID = 0x8613); the module is served by the Cypress generic USB device driver; the Cypress generic USB device driver allows Cypress firmware update tools (Cypress Console, Cypress Control Center) to work with the Cypress EZ-USB FX2 microcontroller on the module;
5. EEPROM switch is set in a way to enable EPPROM connection to USB FX2 microcontroler; Cypress firmware update tools can read and write the EEPROM.

Using Cypress firmware update tools with generation 2 modules does require a recovery boot, in order to force enumeration as Cypress generic USB device driver.
On the other side, using Cypress firmware update tools with generation 3 modules does not require a recovery boot. This is possible because the original Cypress generic USB device driver (in case of a recovery boot) and the Trenz Electronic USB FX2 device driver ( in case of a regular boot) are both Cypress driver. Trenz Electronic USB FX2 driver derives from the original Cypress generic USB device driver.
EEPROM switch shall always be on during EEPROM programming.
The firmware update procedure is similar for both generations. The following table summarizes the main differences.