Many times I need to snif and log on a file the activity between two nodes that talk over a full-duplex UART (separate TX and RX lines). Just...

Many times I need to snif and log on a file the activity between two nodes that talk over a full-duplex UART (separate TX and RX lines). Just an example, consider a host MCU that talks with a modem through AT commands. It's a half-duplex protocol because the MCU sends the AT command and the modem replies. However the modem is able to send URC messages that can be emitted at any time. ...

I'm studying datasheet of SST26VF080A. It's a SPI Quad Flash memory in standard 8 pin package. I'm not sure I correctly understood the quad...

I'm studying datasheet of SST26VF080A. It's a SPI Quad Flash memory in standard 8 pin package. I'm not sure I correctly understood the quad mode. It appears to me two quad modes are supported: SPI Quad mode (IOC=1 in Configuration Register) and SQI mode (after sending Enable Quad I/O command). For example, after setting IOC bit in Configuration Register I can use SQOR command (SPI Qu...

Hello Does anyone know of a nice text on finite state machines and their software implementation on embedded systems? I'm looking for some...

Hello Does anyone know of a nice text on finite state machines and their software implementation on embedded systems? I'm looking for some theoretical background and design methodology. A few examples of "C" implementation would be a nice but not really needed. I'm not looking for a recipe or code but for a more formal explanation on the workings of FSM. Thanks jmariano

The unit only really needs one serial port, but it is more convenient to have two connectors, so I guess it needs to ports. One port will only...

The unit only really needs one serial port, but it is more convenient to have two connectors, so I guess it needs to ports. One port will only receive and the other only transmit, no handshaking. The function is pretty simple. A sensor sends a line of about 50 chars, at 9,600 bps, once per second. This box counts 20 lines and adds a header. So nothing fancy is required of the MCU. There ...

I think you already know this trick: connect DE/RE signals of RS485 half-duplex transceiver to TX *negated* signal from UART and connect TX...

I think you already know this trick: connect DE/RE signals of RS485 half-duplex transceiver to TX *negated* signal from UART and connect TX input of transceiver to GND. If the bus is not driven by anyone, A signal goes high and B signal goes low thanks to the pull-up/down resistors. The trick uses the fact that the undriven bus and transmitting 1 is the same thing: A is high and B is...

I am amazed at how commonplace this is becoming -- and how shortsighted the implementations! Have YOU considered how a user CLEANS the...

I am amazed at how commonplace this is becoming -- and how shortsighted the implementations! Have YOU considered how a user CLEANS the panel? If the device can be turned OFF, then they could resort to that avenue to ensure cleaning actions aren't interpreted as "commands". But, if it *can't* be (or, if the user decides they want to clean the panel NOW -- for whatever reason), then yo...

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...