I have bought few Blue Pills on Aliexpress. I expected to receive boards with some of known clones. But what I get does not look like any...

I have bought few Blue Pills on Aliexpress. I expected to receive boards with some of known clones. But what I get does not look like any clone that I have heard of: - Cortex M4 with no FPU - 32k RAM - 128k flash - set of devices like STM32F103C8T6 Chip seems to be resonable compatible, but I noticed notable difference in I2C peripherial: bit 14 in OAR1 (own address register 1) se...

There is another STM clone on the market. Namely, one can buy board with chip marked Air32F103. Internet says that this is rebranded MH32F103....

There is another STM clone on the market. Namely, one can buy board with chip marked Air32F103. Internet says that this is rebranded MH32F103. There is datasheet in Chinese which says that there are 5 variants of MH32F103, smallest one with 32kB RAM and 128kB flash (that is what is sold as Air32F103) but there are bigger with RAM going up to 96kB and flash up to 1MB. I got Blue Pills whi...

I don't recall the TI designator, but they make some DSP parts that have peripherals like MCUs. I know that some time back, ARM made a push into...

I don't recall the TI designator, but they make some DSP parts that have peripherals like MCUs. I know that some time back, ARM made a push into DSP territory by adding some DSPish instructions to I believe it was the CM3 devices, or maybe CM4. Anyone here use these crossover devices? What sort of apps? Why did you pick that device over others? -- Rick C. - Get 1,000 miles of fr...

I often use newlib standard C libraries with gcc toolchain for Cortex-M platforms. It sometimes happens I need to manage calendar time: seconds...

I often use newlib standard C libraries with gcc toolchain for Cortex-M platforms. It sometimes happens I need to manage calendar time: seconds from 1970 or broken down time. And it sometimes happens I need to manage timezone too, because the time reference comes from NTP (that is UTC). newlib as expected defines a time() function that calls a syscall function _gettimeofday(). It should...

ISTR playing with de-encapsulated DRAMs as image sensors back in school (DRAM being relatively new technology, then). But, most cameras seem...

ISTR playing with de-encapsulated DRAMs as image sensors back in school (DRAM being relatively new technology, then). But, most cameras seem to have (bit- or word-) serial interfaces nowadays. Are there any (mainstream/high volume) devices that "look" like a chunk of memory, in their native form?

I want to understand impact of buses/wait states on Cortex-M preformance. It seems that documentation about this seem to be scatterd or...

I want to understand impact of buses/wait states on Cortex-M preformance. It seems that documentation about this seem to be scatterd or unavailable (I would appreciate pointers to appropriate documentation). I was unable to find answers in documentation so I did some testing. Below part of my results. I run tests on STM32F030, STM32F103, STM32F407, STM32411 and two chinese clones, namly ...

I am using laptops to control test fixtures via a USB serial port. I'm looking at combining many test fixtures in one chassis, controlled over...

I am using laptops to control test fixtures via a USB serial port. I'm looking at combining many test fixtures in one chassis, controlled over one serial port. The problem I'm concerned about is not the speed of the bus, which can range up to 10 Mbps. It's the interface to the serial port. The messages are all short, around 15 characters. The master PC addresses a slave and

I've been considering a Greenpak device or two or even three, in a respin of a new design. I've identified three functions that the Greenpak...

I've been considering a Greenpak device or two or even three, in a respin of a new design. I've identified three functions that the Greenpak devices could replace on my board, but not all in the same part! LOL I'd like to discuss this design with an FAE or salesperson, but I can't seem to get any replies. The Renesas website was clearly created by pointy haired bosses in legi

I wanted to implement an I2C bus recovery during initialization. The reason is well known in literature[1]. I read the function...

I wanted to implement an I2C bus recovery during initialization. The reason is well known in literature[1]. I read the function i2c_generic_recovery[2] of Linux kernel, but I don't understand one thing. The bus recovery is necessary to bring a slave to the end of a byte transmission that could be interrupted for some reason. However the slave could be transmitting 0xFF, so why the abo...

I have a test fixture that uses RS-232 to communicate with a PC. It actually uses the voltage levels of RS-232, even though this is from a USB...

I have a test fixture that uses RS-232 to communicate with a PC. It actually uses the voltage levels of RS-232, even though this is from a USB cable on the PC, so it's only RS-232 for maybe four inches. lol I'm redesigning the test fixtures to hold more units and fully automate a few features that presently requires an operator. There will now be 8 UUTs on each test fixture an