I am looking at the pin-out here: http://www.ti.com/lit/ml/slau536/slau536.pdf and can't find p1.0 and p1.1. Where are they?
The reason (perhaps, stupid) why I started looking for these two pins is because I need to connect RX and TX of a UART somewhere on the launchpad, and p3.3 and p3.4 did not work, and on some loosely related pinouts of other boards such as this: http://energia.nu/Tutorial_DigitalReadSerial.html p1.1 is RXD and p1.2 is TXD (not sure what's the difference between RX and RXD, assuming for now they are the same). So I thought maybe I try these pins and try my luck there? And now I can't find them.
BTW, the pinout shows that p3.3 and p3.4 are UART RX and TX on BoosterPack standard, which I don't have, and on the launchpad these pins are UCA0RXD and UCA0TXT (also, they are apparently UCA0SOMI and UCA0SIMO). I don't know yet what these abbreviations mean, and also, why there are two sets of functions on the same pins and how to switch between them.
My launchpad (in subj) documentation says it supports up to 4 hardware UARTs. Where? And why then is there a UART on booster pack?
Maybe p1.1 and p1.2 are taken for the launchpad's onboard backchannel UART?
If you want to know where every pin goes on this board then you should look at the schematic in the User's Guide. But more importantly, you should get familiar with the datasheet for the microcontroller on the board.
You don't see P1.0 and P1.1 because those pins are not brought out to the booster pack headers (connectors). Those pins are used within the launchpad board for something else. (They are not even UART pins as you hoped.)
P3.3 and P3.4 is the only UART connection that you have available through the booster pack headers. The other UART is on P4.4 and P4.5 and those pins aren't brought out through the headers. So you should probably try to get P3.3 and P3.4 working. Did you download TI's example software for this launchpad? There is probably an example program that uses the UART.
P3.3 and P3.4 are multiplexed as are many GPIO pins on typical microcontrollers. These particular pins can be configured as GPIO, a UART, or an SPI port. SOMI and SIMO are abbreviations related to the SPI function. Your code will have to configure these pins for the UART function. Read the datasheet and study the example software to learn how to do this.
I'm not sure where you saw four UARTs. The microcontroller on this particular launchpad has four serial interfaces but only two of those interfaces are designed for UARTs. The other two serial interfaces can be SPI or I2C.
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I'm learning about embedded systems and have an idea about one small project and I want to use Cortex M0+ based MCU STM32G081KBT6. I saw a lot of tutorials with this MCU type, but all of them are based on developer board and with them it is very simple to upload code with USB cable. I want to make my custom PCB for this. So my question is what I have to do so I can upload my code to this microcontroller?
From a datasheet I think I have to use SWDIO (PA13) and SWCLK(PA14) ports for Boot, but if someone can help me do I have to use also some resistors, can I make it USB to wire transfer with this, or I have to use some external device to make it possible? Or there is some easier and better solution to upload code from my laptop to microcontroller?
Thanks for the replies.
There two main options:
SWD
Implement an SWD programming connector. Basically the pins GND, SWDIO, SWCLK and preferably 3.3V are made available. No resisters are needed. You can fit a 4 pin header, an official 10 pin SWD connector or just 4 pads (for connecting using an adapter with pogo pins).
This option requires an SWD debug adapter like ST-Link or J-Link. In addition to uploading firmware, this option supports debugging.
USART
Make the USART (RX, TX) pins plus GND and 3.3V available on the board. This option requires a USB-to-serial adapter.
It's also possible to use I2C or SPI instead, though there are no standard solutions for connecting to your board that I'm aware of.
USB isn't an option for this particular chip. It is supported on many of the more expensive STM32 chips though.
I strongly recommend the first option. It is far more versatile than the other options. And an ST-Link adapter isn't expensive.
Details regarding the bootloader capabilities and pins:
https://www.st.com/resource/en/application_note/cd00167594-stm32-microcontroller-system-memory-boot-mode-stmicroelectronics.pdf
I'm a beginner in the embedded system development world.
I would like some clarifications on the following questions.
Is every pin of a microcontroller (from here after referred to as mc) associated with a register?
Is it an one to one relationship?
How are ports (or groups of pins) assigned inside the mc?
Is it only possible to set a single pin low or high only?
No. Some pins are not associated with a register at all, e.g. Vcc and GND and if they do not have a dual use as a GPIO it also applies to clock/oscillator and reset pins.
If a pin is associated with registers, it is usually associated with several ones: one for determing the IO direction, one for reading the input, one or more for setting the output. For I2C, SPI, UART pins, the associated is indirect, i.e. the register mainly control the I2C/SPI/UART controller, which in turn is associated with the pin.
I don't understand the question
A GPIO pin can be set as input, as output in high state (delivering current or with a weak pull-up), as output in low state (sourcing current or with a weak pull-down) or in open-drain state (often similar to input mode). A pin can also be configured to be used by one fo the I2C/SPI/UART controllers or as DAC (outputting a variable voltage between GND and Vcc).
In addition to fundamental stuff like supply and clock pins, a MCU got numerous hardware peripherals internally. A hardware peripheral being something like a piece of GPIO (general-purpose input/output), ADC, UART, SPI etc. Each such hardware peripheral has a number of possible pins to which its functions can be routed.
Traditionally, these were pretty much fixed - if you wanted UART Tx then you would always get it on some fixed pin number, take it or leave it. Nowadays, most MCUs are quite flexible internally, allowing you to re-route hardware peripheral functionality to almost any pin you like, variably.
In either case, several hardware peripherals could share the same pin, and then it is MCU specific which one that takes precedence. For example GPIO could be present on the pin by default, but if you enable UART then maybe the MCU states that you get UART Tx on that pin instead.
As for the hardware peripheral called GPIO, they are almost always grouped in ports, where each port consists of a number of pins. Most often, port registers are either 8 bits or the size of the CPU's word length. Each bit in the various port registers corresponds to a pin.
You'll have a port data register, which is the actual read/write to the pin, a data direction register stating input or output, and then various other registers for interrupts, pull resistor enable etc etc.
Not all pins but all IOs (Input/Output) have a specific register.
Each IO has a specific group of registers. Bu also some registers may include specific bits which effects an IO or all IOs.
It depends of design of micro controller.
Yes it is.
I strongly recommend you to read some embedded hardware/software books(for example Newness Know It All books for embedded systems) and datasheets.
I am learning about ARM development on my STM32F7 Discovery Kit (w/ STM32F746NGH6 Microcontroller) and I'm trying to write a "blinky" program without using high level libraries.
Reading the documentation, I couldn't figure out which MCU pins are all those onboard LED's connected to? What is the right document to check?
Looking at the board I can see some LEDs (LD1, LD2, ...), but how can I reach them in program? I don't see them in header files and if they are controlled via GPIO pins, how to I know which ones?
In the user manual there's no mention of any LED, except in the electrical schematics (where none of the LEDs is connected directly to the MCU afaik- they serve mostly as hard-wired board status indicators).
Is it possible that an advanced board like this doesn't have a single general purpose LED on it?
From the schematic in that document, it looks like you should be able to use LED LD1 on PI1 (GPIO port I pin 1).
Download the STM32CubeF7 software package. It should include a blinky program example specifically for your board. Then see which LED/pin they use in the example program.
I'm a newbie in embedded programming.
Now I'm trying to understand a datasheet for Telechips 8001S.
What is the difference between SPI(Serial Peripheral Interface) and GSB(General purpose Serial Bus)?
Thank you.
google is your friend...
Telechips GPSB appears to be their spi implementation (and one or more other serial protocols) master or slave with dma. Spi is the protocol, call it a standard or not but there are a large quantity of devices that support it, GPSB is the logic/peripheral in the chip that you can use to connect to spi masters or slaves (you can always bit bang on gpio of course). Looks to have dma and probably other features.
I didnt find the 8001 nor the 8010 docs, but did find one that was enough to understand.
On some ti products you may find the USI, universal serial interface, the name for their uart, spi and i2c peripheral.
Some ftdi chips have MPSSE, which can be programmed to implement quite a few protocols, jtag, spi, i2c, mdio, roll your own.
Other vendors may simply call the peripheral UART, SPI, I2C.
Its just a name that marketing or engineering or a combination of the two at that company chose for the peripheral within the chip.
I am a newbie in this subject and want to learn how to embed codes into MSP430.
I have a breakout board MSP430-H5438 and I am not using JTAG interface.
I have the IAR generated codes (hex files) ready (ADC, SPI interfaces), however I could not load them into the IC.
I am using a USB-UART bridge to connect device to PC, BSL scripter for software, but there is no result.
Is it a wrong way to connect MSP430 to PC without JTAG interface? Am I running in circles here?
Thanks in advance.
BSL should work but you need to connect not only the TX and RX but also you need to have DTR connected to RST and RTS to TEST. If your USB-UART interface only has TX and RX (which is often the case) then it will not work with BSL.
Note that the MCU on that board supports not only the regular (and expensive) JTAG but also the newer SBW interface. This means you can get the $4.30 Launcphad and program your board using the programmer that is included on the Launchpad. This will let you do anything you can do over the regular JTAG and is highly recommended over BSL since it will give you hardware debugging functionality. And the Launchpad can be useful on its own too.