README.md

MSP430i2041 Proto Board (SLAU335)

For testing SLAU335 devices family.

The proto-board for the MSP430i20xx family is target for the application specific devices with TSSOP-28 package. This is a special family designed for metering and are equipped with extraordinary 24-bit D/A, so there are not so many options available.

This board offers a set of configurable options that will be covered by this documentation.

The pictures shows a 3D model of this prototype board:

These are the features:

• Support for the single series of chips having a TSSOP-28 pin-out: the MSP430i2020, MSP430i2021, MSP430i2030, MSP430i2031, MSP430i2040, and the MSP430i2041.
• Standard 14-pin JTAG connector.
• JTAG bus access for a logic analyzer.
• Configurable support for JTAG and Spi By Wire.
• Support for power supply from JTAG connector or internal 3.3V regulator using a Micro USB cable.
• Reset button.
• A very basic analog voltage support is provided for ADC use.
• Test led on P2.2 configurable by jumper.
• All IO ports wired to accessible header pins.
• Header pins for VCC, USB +5V and GND.

Users Guide

The following points describes general use of this board.

Configuring the Board According to MCU model

This board supports all distinct MSP430i20xx parts of this family having TSSOP-28 package. Although they have almost identical pin-out, note that the analog frontend is different and the part model determines the number of existing analog channels.

Note that there is a dedicated jumper set for the analog inputs which are differential. So for example, if you solder a MSP430i2031, only 3 analog inputs are available, so two inputs are not available and pins have no other usable function.

Like the picture above, you are allowed to solder a shorter jumper to avoid improper use of channels that are not available.

External USB power supply

To use the external power supply connect a powered µUSB cable into J1. For this case the switch SW1 will control the power supply.

Before connecting a JTAG cable into J7, ensure that the VSEL jumper shorts the Vref position.

Powering from the JTAG tool

If you are just connecting the proto-board without additional hardware, then the power supply of the emulator will be enough to supply the installed chip and it is easier to use the emulator as source.

For this option just move the jumper on VSEL to the Vtool position and connect the JTAG emulator to the J7 JTAG connector. When the JTAG is connected and running it will supply the board.

Note that the switch SW1 and the +5V jumper has no effect on this configuration and should be left disconnected or turned off.

Selecting JTAG or SBW Modes

Since pin-outs may differ for different debug emulators the board offers two different options in the J3 jumper set.

The silk screen indicates four jumpers that needs to be shorted for the standard JTAG interface.

If you choose Spy-Bi-Wire, only two jumpers are necessary.

These options are mutually exclusive: although possible, it is not recommended to enable multiple options at the same time.

JTAG Configuration

For the JTAG mode the four jumpers connects the following pins:

• TDO → TDO (P1.3)
• TCK → TCK (P1.0)
• RST → RESET
• TEST → TEST

Please make sure that no other connection is made on P1.0, P1.1, P1.2 and P1.3 while using the JTAG bus as this could cause a conflict with the emulator.

Spy-By-Wire Configuration - TI pin-out

TI SBW uses the following connections:

• TDO → RESET
• TCK → TEST

Connection for the Logic Analyzer

During firmware development it is very important to have the ability to read out the digital waves for the JTAG bus, since timing is a very critical factor.

This board offers an access to all signal required for debug:

Reset Button

The Reset button can be used to restart the device. It is not advised to interrupt a running JTAG connection by pressing this button. Some references states that attached MCU may enter an undefined state.

Other Voltage Supplies

The board exposes all power supplies through jumpers. It is advised to follow good practice rules, as these are unprotected. The +5V pins are connected to a USB bus or power adapter and is only available if supplied by an USB cable. Low quality power sources may be a cause of issues.

Using the LED function

To use the LED, just short the LED_P1.2 jumper.

A test program for the LED test could be:

#include <msp430.h>

void Delay()
{
	long counter = 0;
	while (counter++ < 5000)
		asm("nop");
}

void MainLoop()
{
	WDTCTL = WDTPW | WDTHOLD;
	
	P2DIR |= (1 << 2);
	
	for (;;)
	{
		P2OUT |= (1 << 2);
		Delay();
		P2OUT &= ~(1 << 2);
		Delay();
	}
}

int main()
{
	MainLoop();
}