December 28, 2016 in C, C++, DIY, ESP8266, Microcontroller, Tips & Tricks by admin
The ESP8266 is a low-cost Wi-Fi chip with full TCP/IP stack and MCU (Micro Controller Unit) capability produced by Shanghai-based Chinese manufacturer, Espressif Systems.
Since 2014, when first came in the attention of the western makers, the documentation became quite available, together with couple of SDKs and firmwares for various programming langauges like Lua, together with the low price, made reasonable easy to develop applications hosted on this tiny chip. Some of this little chip’s features:
- 32-bit RISC CPU: Tensilica Xtensa LX106 running at 80 MHz (can be overclocked)
- 64 KiB of instruction RAM, 96 KiB of data RAM
- External QSPI flash – 512 KiB to 4 MiB (up to 16 MiB is supported)
- IEEE 802.11 b/g/n Wi-Fi
- Integrated TR switch, balun, LNA, power amplifier and matching network
- WEP or WPA/WPA2 authentication, or open networks
- 16 GPIO pins
- SPI, I²C,
- I²S interfaces with DMA (sharing pins with GPIO)
- UART on dedicated pins, plus a transmit-only UART can be enabled on GPIO2
- 1 10-bit ADC
Although developing software to be hosted on it isn’t such a big challenge like it used to be due to the plenty of information available on the internet, debugging the code running on the MCU is a different story. Luckily, at the Attachix blog there is a series of articles about writing software for this MCU, and in the 4th article the owner was nice enough to describe how to set up step-by-step debugging of the code either by command line or even from Eclipse IDE. Please follow this link for the entire article.
May 9, 2016 in ARM, C, C++, Hardware, Linux, Microcontroller, Programming, STM32, Tips & Tricks, Tutorial by admin
In some previous topics (here and here) I wrote about some cheap development boards which can be acquired from EBay or Aliexpress. Since System Workbench for STM32 is freely available for a while now, let’s see how can we use it to generate a project, compile it, upload it to a board and debugging it step by step. We’ll use for this the board I got from EBay, but it works the same with the any STM32 other board I have and also with some self-made ones.
For being able to install firmware on the board and debug it, first we need to have a hardware part which will sit between the computer and the board. There are various models and versions of these jtag debugers and they can be ordered online or found pretty cheap on ebay (clones). Another way to get hold of one of these is to have a development board which comes equiped with JTAG adapters, like the STM32 discovery series of boards. Some of these JTAG debuggers allow even breaking apart the JTAG debugger from the development board itself (LPCXpresso series, the nucleo boards).
Regardless of which JTAG interface is used, it should be one which is known to work with OpenOCD, as we’ll use OpenOCD for debugging. In our case we’ll use the stm32f4 discovery board’s stlink2 side. However, Before using it as a JTAG debugger, we need to disconnect the STLink part from the discovery board, by removing two jumpers. Once that is done, the STLink itself won’t be connected to the discovery board and it’s SWD header can be connected to any other board. Read the rest of this entry →