STCOM10 datasheet(30/58 Pages) STMICROELECTRONICS

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Description

STCOM

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DocID028515 Rev 1

Table 6 shows the values of the boot pins for each boot mode.

1.13

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.

1.13.1

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.

1.13.2

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.

Table 6. Boot modes and BOOT0/1 pin values

Boot mode

Boot mode value

BOOT1

BOOT0

Normal boot

0x2

Customer OTP write

0x0

Unlocking

0x1

Low power

0x3

STCOM10 데이터시트(PDF) 30 Page - STMicroelectronics