This document describes the features of the SystemMemory boot mode developed for STR73x Flash microcontrollers to provide all the basic functionality to support programming of the embedded Flash. It will describe its general features, and then move on to specific features of the UART boot mode.
The document details the SystemMemory boot mode developed for STR73x Flash microcontrollers, which allows initializing Flash programming via a serial interface when the device is woken up in this specific mode. It explains how the system boot is performed from the SystemMemory sector and how to load code into internal RAM.
| Instruction Set | THUMB |
|---|---|
| CPU Mode | Supervisor |
| Input Clock Range | 4 to 8MHz |
| System Clock Range | 12 to 24MHz |
| UART Receive Pin | UARTO_RX |
| Downloaded Code Start Address | 0xA0000000 |
| Acknowledge Byte Value | 0x95 |
The device enters this mode if the mode pins are configured with M0=0, M1=1 as the hardware reset pin transitions High at the end of a hardware reset.
The minimum baud rate determined by the maximum count capacity of Timer Base 0 when measuring the zero byte is 1648, with the lowest standard Baud Rate being 2400.
The SystemMemory code receives a specified number of bytes, currently defined as 128 bytes for UART.