STCOM Datasheet, PDF (30/58 Pages) STMicroelectronics – Powerline communication and application system-on-chip

Description
Table 6 shows the values of the boot pins for each boot mode.
Table 6. Boot modes and BOOT0/1 pin values
Boot mode
Boot mode value
BOOT1
Normal boot
0x2
1
Customer OTP write
0x0
0
Unlocking
0x1
0
Low power
0x3
1
STCOM
BOOT0
0
0
1
1
1.13
1.13.1
1.13.2
System reprogrammability
The STCOM supports both in-system and in-application programming (ISP and IAP) modes
through the use of the embedded Flash and an external non-volatile memory (NVM). If the
external NVM contains two firmware copies, it's also possible to roll back to the previous
firmware version in case of firmware malfunctioning. The change of firmware to enable
different functionalities will require a complete reset of the device if the customer does not
implement its own bootloader.
In-system programming (ISP)
The ISP mode allows the user to erase and program the embedded Flash through the JTAG
port. This mode can be inhibited to enhance the security level of the device.
In-application programming (IAP)
The IAP mode allows the application on board to store in an external non-volatile memory
the firmware to be downloaded into the internal embedded Flash. The firmware image in the
NVM is copied into the internal embedded Flash at the power-on. The boot code inside the
device takes care of the integrity check, embedded Flash erasure and programming. IAP
can be done using the power line or by the local upgrade port. The customer can also write
its dedicated bootloader to perform IAP with the activation of a specific security level.
30/58
DocID028515 Rev 1