LIFI, the indoor gps and data highway, still with slow adoption
It highlights the benefits: high speed data transfer, unlimited bandwidth, privacy, robustness to interference, human health, …. However, in reality, despite the buzz, no large-scale deployment has happened yet.
Facilitate compatibility across the IoT network. IoT Gateway ensures this by supporting a number of communication protocols like Zigbee, 6lowpan, Bluetooth, WiFi, LoRA, Zwave
All the devices that need to be monitored or controlled have relevant sensors…[Read more]
Countless projects in North America, Europe or Asia are currently using ST’s STM32 microcontrollers (MCU), Nucleo development boards, Time of Flight sensors, among many of its other components. ST’s partnerships with many companies have already pioneered the…[Read more]
LoRa™, which is short for LoRaWAN (Long Range Wireless Area Network) is a type to LPWAN (Low Power Wide Area Network). Developed by Semtech and governed by the LoRa Alliance™, of which ST is a member. LoRa™ uses sub-gigahertz bands to connect devices which…[Read more]
At its CES 2018 press conference, Qualcomm discussed a strategy that expands its Serviceable Addressable Market (SAM) from $32 billion in mobile to over $150 billion in several key growth markets, including RF ($20B), automotive ($16B), IoT and…[Read more]
Need to save a small amount of data on external non volatile mem. But the board we use has serial flash rathern than eeprom. for flash, you can write a bit from 1 to 0 but not the other way around unless you erase the sector. But erase takes time.
When we suspect if a io pad is broken, io curve tracing can help. Apply dc voltage to pad and ground and check current. VI currrent should be as shown for a normal pad. The rapid increasing currents at both pos and neg voltages are due to io esd…[Read more]
It is basic but sometimes forgotten. If you see a two FFs as synchronizer, it may or may not work. It depends on if the input signal is at least two cycles long to allow the synchronizer to capture it. Modern CDC tools such as spyglass can flag the issue.
Notice there is mem scrub rate calculation xls at this site. You can use it to cal how often to scrub mem based on radiation env, mem type/size, etc. idea is to avoid errors which are not correctable. Doesnt necessarilly mean single error since you may used…[Read more]
Once uart start bit is detected, receive side can count how many bits it receives and keeps going for many bits, right? No.
Finally understand it why i debugged a uart issue myself. As a matter of a fact, what we really need is a new start bit. So we need a stop…[Read more]
Use low power msp430fr58 and board current too high
Msp430fr58 has excellent low power modes. Standby is less than 1ua and wake up latency is < 10us. But be careful of your board. For dc to dc converter, is it LDO or switch regulator. Power efficieny at different current levels. Also pin…[Read more]
A typical xtal osc is shown. Two caps and xtal are external to chip. The op amp is inside chip. To board designers, that op amp driving strength is not fixed. They normally have higher driving strength at bootup to make sure xtal osc…[Read more]
3.3-10k is normally used for pull up. Main reason is RC rise time. Another consideration is chip internal pull up/down. They are normally around 50k but with big variation. Sure they can be turned off later by fw to avoid conflict of board pull…[Read more]