MSP432E411Y: Example code for ROM_UpdateUART and ROM_UpdateUSB

Hello Sven,

We don't have specific code examples that show how to use ROM_UpdateUART and ROM_UpdateUSB APIs, but I can provide a brief summary of what to do before these APIs are called:

For USB:

• Terminate the USB device from the bus
• Disable Master interrupt
• Clear/Disable all interrupts

• Enable USB Clock and wait for about a second.
• Re-enable Master interrupt
• Call the API ROM_UpdateUSB(0)

For UART - The function SoftwareUpdateBegin in the file "./source/third_party/lwip/ports/msp432e4/utils/swupdate.c" demos the following steps for Ethernet.

• Clear/Disable all interrupts
• Call the API ROM_UpdateUART()

Hope this helps!

Thanks,

Sai

Hello Sai,

thank you for your answer. I already had a look into the bootloader examples and derived (almost copied) the following code:

#define TIMESTAMP_CLOCK     120000000ULL

MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);

/* Set GPIO PA0 and PA1 as UART. */
MAP_GPIOPinConfigure(GPIO_PA0_U0RX);
MAP_GPIOPinConfigure(GPIO_PA1_U0TX);
MAP_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);

/* Configure the UART for 115200, n, 8, 1 */
MAP_UARTConfigSetExpClk(UART0_BASE, TIMESTAMP_CLOCK, 115200,
                        (UART_CONFIG_PAR_NONE | UART_CONFIG_STOP_ONE |
                                     UART_CONFIG_WLEN_8));
/* Enable the UART operation. */
MAP_UARTEnable(UART0_BASE);
/* We must make sure we turn off SysTick and its interrupt before entering
 * the boot loader! */
MAP_SysTickIntDisable();
MAP_SysTickDisable();
/* Disable all processor interrupts. Instead of disabling them one at a
 * time, a direct write to NVIC is done to disable all peripheral
 * interrupts. */
NVIC->ICER[0] = 0xffffffff;
NVIC->ICER[1] = 0xffffffff;
NVIC->ICER[2] = 0xffffffff;
NVIC->ICER[3] = 0xffffffff;
ROM_UpdateUART();

According to SPMU363 (Tiva™ C Series TM4C129x ROM USER’S GUIDE) the UART peripheral must be configured and operational before calling ROM_UpdateUART. I checked the UART by sending a few symbols. It works at the expected bitrate of 115200bit/s.

Unfortunately this code is not working at all on our MSP432E411Y hardware (BSL scripter gets no response from BSL neither with nor without DISABLE_AUTO_BAUD option).

After a mass erase I get the blinky example programmed and running, thus connection seems OK.

Honestly I cannot imagine, that there is no code available at TI. Someone must have done testing on the ROM_UpdateUART function.

I already spent an unexpected amount of time on getting the MSP432E programmed via UART and it is still not working. The only thing I could get till now is programming our hardware with the blinky example after a mass erase via the MSP-EXP432E401Y's UART and BSL scripter. Programming our real software on the hardware the same way failed - BSL scripter reported everthing ok after 4 minutes, but the application ended in an endless loop. (The same application is running fine after programming via USB/LMFlasher or JTAG/CCS.)

I'm really frustrated.

Please ask the developer for a working code example!

Hello Sai,

the reason for our application not being programmed correctly by BSL scripter might be a function in RAM (__attribute__((ramfunc))) resulting in follwing entry in the .txt file:

@23cd0

Maybe BSL scripter is unable to deal with it.

Hello Sven,

Thanks for the updates! I will talk to the development team to investigate the issues that you reported.

Regards,

Sai