Yeah. Those pins are beautifully aligned a very precise 0.1” from where they are supposed to be…
Pro tip: Print out your design and put your components on it so that you can check the design.
Meta pro tip: Follow your pro tips.
Anyway, that’s not the only problem; it turns out that the power and LED parts of the connector are right underneath the end of the board, so you can’t use a normal header on them (you could use a right-angle one if you wanted), so I did a new revision of the board with 1.0” rather than 1.1” for the ESP and extended the board so the connectors are out on the end. That’s on the slow ship from China right now.
Bus Pirate prototype “Ultra” v1c will use a 0.5mm flex cable (FFC/FPC) to connect the display board. Of course we could just order the standard parts from Mouser or SZLCSC, but rooting around on Taobao is fun and gives a better idea of the sheer range of stuff out there. We picked up this sourcing habit from open-source developer communities. Members frequently use these overseas markets to source niche flex cables for everything from retro handheld consoles to secure hardware authenticators for the fastest payout online casino networks. Here’s some Chinese vocabulary that helped us order parts.
Cables that are connected 1:1, pin one of one connector is wired to pin 1 of the other connector, are called 反向. Cables that are connected 1:N, pin one of one connector is wired to the highest number pin of the other connector, are called 同向. We ordered the wrong version of the 1.25mm display cable for v1b, but fortunately the crimps can be carefully removed and replaced in reverse order. This won’t be an option with the flex connector.
Most FPC/FFC connectors are available in two types. Metal contacts on the bottom of the connector slot are called 下接. Metal contacts along the top of the connector slot are called 上接.
Orientation is really important because FPC/FFC cables generally only have contacts exposed on one side of each end. FPC/FFC cables are also available in 反向 / 同向 (1:1/1:N), meaning the exposed contacts are on the same side or opposite side of the ends. We’ll post some photos of these cables when they arrive.
Daumemo has been working on a DIY signal generator based on an AD9833 IC:
In this post I am going to continue with the DIY signal generator based on the AD9833 IC where I have left in the previous part. Earlier, I have talked how I had built my first analog signal generator’s stage – variable gain amplification circuit. Usually, a generator needs to have an ability to change not only the signal’s amplitude, but also its offset. So, today I will walk you through a circuit which adds an offset to the DIY generator’s output signal.
More details on his blog. See part 1 of this series for the analog signal generator’s stage.
The Bus Pirate prototype “Ultra” v1b has a 10 pin 1.25mm connector for a display daughterboard. We wanted a more dynamic way to keep track of the pinout and other handy information like pin states and voltage levels.
There are various reference stickers and labeled probe cables for the Bus Pirate v3 and v4, but a display frees us from strict pinout conventions and makes setup a lot easier for new hackers. More on the display below.
I’ll start with the Arduboy its self. I wanted to make a small Arduboy that anyone with basic soldering skills could make. I don’t think its the easies of boards to solder but its the only way I could make it small enough and have all the features I wanted. I just went with the standard SSH1106 0.96″ screen that most people use in their homemade builds. The buttons I went with are the ones I’ve been using on my other RetroPie builds in the past. They are soft touch but they are not mushy like some are and have a small foot print.
Bus Pirate prototype Ultra v1b uses a common, cheap USB C connector and we are in love!
Micro B connectors are a nightmare. Very inconsistent footprints, poor materials and build quality, and very weak mounting supports. Often the leads are hidden under the housing and conceal pesky shorts. Almost every Micro B connector we hand soldered eventually broke off the board and usually took some traces with it.
USB C solved all these issues! Soldering it is an absolute breeze. Leads are easily accessible and friendly to solder. It’s made of decent materials, and the footprint seems to be pretty standardized across the market. The mounting posts are solid and strong, this connector isn’t going anywhere.
Here’s how we connected it on the v1b hardware. The footprint was made by Sjaak at SMDprutser and is in our git repo.
App note from Vishay Siliconix, giving us tips on powering FPGAs. Link here (PDF)
An FPGA is a device that offers many logic elements – up to 1 million gates in a single device at this writing – as well as other functionality such as transceivers, PLLs, and MAC units for complex processing. FPGAs are becoming very powerful, and the need to power the devices effectively is a key, if often underestimated, part of the design. A straightforward power supply design process can significantly reduce the number of required design iterations for the OEM designer.
Today we finished stuffing the first Bus Pirate “Ultra” v1b board. This includes the updates we posted this week, and a few other improvements from v1a:
Various connection changes to optimize use of the FPGA
The new power supply and voltage measurement concept are both tested and working on the new hardware. The new USB C connector is extremely solid and is a dream to solder, we’ll never look back.
Next we’ll work on getting the display going. So far it powers up and no smoke escapes.
The Bus Pirate Vpullup pin supplies a voltage to the on-board pull-up resistors. In the “Ultra” hardware it also powers the external half of the bi-directional IO buffer.
MOSI
CLOCK
MISO
CS
AUX
AUX2 (formerly ADC)
Vpullup
AUX4 (formerly 3.3Volts)
0.8-5.0Vout (formerly 5.0Volts)
GND
So far we’ve added voltage measurement to every IO pin and removed the dedicated ADC pin. We also replaced the fixed 3.3volt and 5volt power supplies with a single programmable output power supply (Vout) capable of 0.8-5.0volts output at 300mA. Today we’re going to reclaim the Vpullup pin and dig into the on-board pull-up resistor system.
After adding buffered voltage measurements to every IO pin, we eliminated the dedicated ADC pin and turned it into a general purpose IO (AUX2). Now we’re going to take a hatchet to the on-board voltage regulators (3.3V, 5.0V) and replace them with a robust programmable output power supply.
Bus Pirate Ultra v1a follows the same pinout as previous Bus Pirates. 5 I/O pins (MOSI, CLOCK, MISO, CS, AUX), a voltage probe (ADC), a voltage source for the on-board pull-up resistors (Vpu), two power supplies (3.3, 5.0volts) and ground. While we were building the prototype it became obvious that a few tweaks could make a much more useful tool.
MOSI
CLOCK
MISO
CS
AUX
ADC
Vpu
3.3V
5.0V
GND
This is the starting pinout. In this post we’ll update the voltage/ADC probe to measure voltage on every IO pin, and free up a pin for general purpose use.
I made some wireless sensors, using BME280 temperature, humidity, and pressure sensors, together with SYN115 transmitter modules. I used these to verify the storage of vacuum sealed “PrintDry” 3D filament storage containers.
Another app note from NXP describing the behavior of the SMARTMOS Dual 24 – 36 V high-side switch devices, at switch OFF when driving inductive loads. Link here (PDF)
These intelligent high-side switches are designed to be used in 24 V systems such as trucks and busses (XS4200). They can be used in industrial (XSD200) and 12 V applications as well. The low RDS(on) channels can control incandescent lamps, LEDs, solenoids, or DC motors. Control, device configuration, and diagnostics are performed through a 16-bit SPI interface, allowing easy integration into existing applications.
App note from NXP about the short-citcuit protection strategies of their MC12XS6 centralized automotive lighting drivers family IC. Link here (PDF)
The MC12XS6 devices include up to five self-protected high-side switches, with its extended protection and diagnostics, to detect bulb outage and short-circuit fault conditions. Additionally, this device incorporates a pulse width modulation control module, to improve lamp lifetime with bulb power regulation at no less than 25 Hz, and address the dimming application (daytime running light).
I decided to build a pogo-pin test jig, and since the approach I came up with was different than the other approaches I’ve seen I thought it would be worth sharing. I’m going to be targeting my laser cutter for fabrication, though I could have chosen to use my 3D printer instead.
Bus Pirate “Ultra” taps an iCE40 FPGA to power a combined Bus Pirate interface and logic analyzer that is infinity hackable. Previous Bus Pirates relied on the hardware peripherals available in a microcontroller, which vary in features and have the occasional bug. With an FPGA we can implement practically any peripheral with all the fixes and hacks we want! SPI, I2C, UART, CAN? Yes! Master or slave? Both! Complex frequency generator? Yup! Full featured JTAG debugger? Don’t see why not!
A big STM32F103ZE (1) microcontroller connects to an iCE40HX4K FPGA (2) through a 16bit bus that can move a ton of data. The fully buffered interface (3) is capable of high-speed signaling from 1.2volt to 5volts. 128Mbit of RAM (4) powers a logic analyzer with a potential maximum speed over 200MSPS. A 32Mbit flash chip (5) stores up to 30 bitstreams with different features that can be loaded into the FPGA by the microcontroller.
This post covers our most recent hacks to the Bus Pirate, created with these goals in mind:
Peripherals that work and can be hacked
Direct interfacing at all common voltage levels
Real-speed bus activity
Built-in logic analyzer
Plenty of space for updates
Continue below to read about the design, or jump to the forum to see the bleeding edge.
Designing a custom lithium battery pack is a fun way to learn about electricity and engineering. Lithium batteries can be used for countless applications including electric bikes, scooters, vehicles, backup power suppliers, off the grid solutions, and much more.
App note from Kionix on the introduction of most common method in determining orientation and rotations in an accelerometer. Link here (PDF)
The fact that accelerometers are sensitive to the gravitational force on the device allows them to be used to determine the attitude of the sensor with respect to the reference gravitational vector. This attitude determination is very useful in leveling or gimballing gyroscopes and magnetometers for use in compass and navigation instruments; determining tilt for game controller applications; and determining tilt or rotation for screen rotation of handheld devices. The method for calculating orientation or rotation depends on the specific application.
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week:
Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
Facebook PCB Friday. Free PCBs will be your friend for the weekend
We’ll contact you via Twitter with a coupon code for the PCB drawer.
Limit one PCB per address per month please.
Like everything else on this site, PCBs are offered without warranty.
We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.
This tuner circuit is a quick prototype which I build to test the RDA5807M FM radio tuner IC. RDA5807M is a single-chip tuner IC with RDS and MPX decoder, and it equipped with I2C interface for control. This receiver builds around Atmel’s ATmega16A 8-bit MCU. The output stage of this design consists of AN7147N, 2×5.3W audio power amplifier.
