Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [bus]

is a subsystem that transfers a plurality of digital bits grouped together to achieve or represent a common function or variable.

0
votes
3answers
81 views

Choosing best bus and protocol for ~128 clients over the wire

I am up to design system with ~128 MCUs communicating to one MCU master. Communication will be bidirectional. Data will be mostly sensor reads, but I plan to use the bus also as communication method ...
0
votes
0answers
78 views

design a modular system, choosing bus and backplane

Our team has developed a several controller boards for our current Projects for over three years. With little modifications we have used this board in several projects so far. Its structure is as ...
0
votes
2answers
81 views

Medium Range Two Wire Bus Recommendations?

Do you have any recommendations for a medium range (~10 meters) two-wire bus? My supply voltage is 24V and I'll have a single master with ~50 slaves connected to it. I've looked into: I2C - Great but ...
0
votes
2answers
38 views

I2C Single Master Multiple Slave

I have a one I2C master and 14 I2C slave devices connected on the bus. I want to clarify the order of things that happen on the I2C bus. Let say the master send an ADDRESS, then all the slave ...
1
vote
1answer
88 views

Splitting a bidirectional bus into two unidirectional ones

I am trying to sniff on a custom SPI-like bus protocol, which uses a unified bidirectional data line instead of separate MISO/MOSI. To make sense of the communication, I need to split it up into ...
1
vote
0answers
64 views

Sawtooth oscillations in bidirectional bus splitter [duplicate]

I am trying to listen in on a SPI-like protocol which is transferred on one busline in both directions (no slave-select). To discriminate which data is sent by which side, I need a bus splitter that ...
1
vote
1answer
60 views

Unnamed bus connections in schematics

I thought I could read schematics, but I have this problem: sometimes there are unnamed signals connected to buses and I don't know where they are supposed to be connected. Example: IC3 pis 14...23 ...
0
votes
2answers
70 views

I2C bus isolation for dummies

Consider you have two devices designed to be I2C masters in same bus. However, only one of them is operational at a time and the other one is completely powered down. In my case the devices have ...
2
votes
2answers
109 views

Multiple slaves with identical address on multi-master I2C bus [duplicate]

I'm planning a hardware design, where I have a main board and multiple peripheral boards. On each of these boards is a microcontroller with I2C, which is the communication bus for the boards. The same ...
2
votes
1answer
123 views

The CAN bus in this vehicle has only one 120 ohm termination resistance. What problems would this provoke?

This vehicle that I've started co-developing is designed with only a 120 termination resistor on the CAN bus. Obviously there should be two of those resistors on two ends of the bus. I will be making ...
0
votes
1answer
61 views

Microprocessor 8085 regains control of the bus

a) immediately after HOLD goes Low b) immediately after HOLD goes high c) after half clock cycle has passed once HLDS goes low d) after half clock cycle after HLDA goes high This question was asked ...
1
vote
1answer
69 views

How many external devices can be linked to a CPU with n address buses and m data buses?

(Hypothetical) Let's say there is a CPU with 8 address lines and 8 data lines. If each external device has 128 accessible registers, how many external devices can be linked? For 8 address lines, I ...
0
votes
0answers
28 views

Bidirectional data bus divided into nibbles not returning correct data - 8051

Since I have 10 I/O lines connected between two microcontrollers (AT89C4051 + AT89S52), I am trying to get away with elegant data transfer. Instead of spending months redoing an entire circuit board, ...
1
vote
1answer
40 views

Purpose of Bus Analyzer

I've not found the clear explanation for the WHY we use the bus analyzer except to capture and analyze data across the communication bus. Yes, we observe message structure, such as command words, ...
0
votes
1answer
67 views

What are the advantages of a wider bus in comparison to those of a higher clock frequency? [closed]

The aim is to increase data transfer rate. I understand each may have some drawbacks and advantages. Frankly I'm not knowledgeable enough to know of many so I'd like some input from others. I know ...
-1
votes
2answers
78 views

How do we find the bandwidth of a bus?

The data width and cycle rate are used to determine the bandwidth, or the total amount of data that the bus can transmit. An 8-bit bus (1-byte data width) that operates at a cycle rate of 1,000 MHz (1,...
1
vote
2answers
49 views

Address bus, databus: how much storage direct accessible

I have a CPU with a 32 bits data bus and a 21 bits address bus. I would like to know how much storage I can connect to this CPU directly. Does this depend on the address bus width, because I can ...
1
vote
1answer
98 views

Unused bits on a DDR3 chip

I have 2 DDR3 x16 chips (MT41K256M16xx) interfaced with an FPGA (M2S150TS-1FCS536). I plan on using point-to-point data & fly-by address/command topologies. I'm using ECC with a 16 bit bus, so 18 ...
1
vote
3answers
437 views

How does the AXI-Interconnect know where to route the data?

Im interested in where exactly the Addresses (BASE_ADDR) set in the "Address Editor" of a Vivado Block Design come into play in the FPGA-Part. I have multiple Blocks with AXI-Lite connected to a Zynq ...
0
votes
2answers
84 views

Are memory-mapped registers actually implemented as real registers?

I am currently trying to better understand microcontroller-architectures and I am particularly studying the ARM cortex-m3 right now. What I have always wondered is, if memory mapped registers are ...
4
votes
1answer
265 views

KiCad Bus on multiple sheets - Are labels the right way to go?

I want to connect bus-lines via several-sheets in KiCAD 5.0 But I don't know whether I got that right. Please consider the following design: Shown in Figure 1 you can see my connection from the chips ...
1
vote
3answers
178 views

Multiple I²C slaves with different addresses VS. using a multiplexer

I'd like to interface a lot of identical I²C sensors, let's say 32, with a MCU that has only 2 I²C busses. I can configure each sensor to have up to 8 different addresses. Hence I can have 8 sensors ...
1
vote
4answers
382 views

CAN Bus on PCB board

Will a CAN bus also work for on-board communication, without twisted pair cabling, between 2 or more microcontrollers on the same PCB board?
3
votes
3answers
1k views

Sampling rate understanding for ADC requirement

So I have this voltage plot. These are voltages corresponding to a current changes on a wire. I am trying to understand the rate of transmission for choosing a ADC to read these analog values. The ...
0
votes
0answers
27 views

LTspice modelling for the end terminal side

So I have this model. I am trying to build a current/voltage converter circuit for a bus carrying current to the other end of the bus, because I need to give this voltage output from the amplifier to ...
0
votes
0answers
32 views

Multi-channel data transmission system for Pixhawk autopilot

I hope to connect multiple Pixhawk autopilots to one PC, to establish a simulation system. In case you are unfamiliar with Pixhawk autopilot, here is a brief introduction: Pixhawk autopilot is an ...
2
votes
1answer
148 views

Terminator in Raspberry Pi CAN-shield

I am planning to connect (at least) two Raspberry Pi + PiCAN2 shields via CAN. I think I understand the concept of a daisy-chained multidrop CAN line, but what about using the 120 ohm resistors for ...
0
votes
1answer
83 views

wide parallel bus

I need to implement a custom 64-bit wide parallel bus interface operating at 100MHz (800MB/s total bandwidth). While there are no ready solutions for this, is it possible to implement such bus by ...
0
votes
0answers
43 views

Propagate data bits with 8 BIT register in ISE SR8RLED

I had some issues propagating the input from the 8 BIT register to the output using the SR8RLED 8 BIT Register in Xilinx ISE. The register has the following parameters: ...
0
votes
1answer
129 views

MAG3110 and MPU6050 on one I2C bus connected to a Raspberry Pi

I am trying to use separate pre-built breakout modules containing a MAG3110 (Magnetometer) (module) and a MPU6050 (gyroscope) (GY-521 module) on one I2C bus connected to a Raspberry Pi. Although both ...
1
vote
2answers
107 views

Bus tapping in Xilinx ISE for 8 bit to 16 bit conversion

I have a processing unit which is controlled by a sequencer/control unit. The agenda of this processing unit is to multiply 2 numbers using 8 BIT registers using the bit shift and add method. Once ...
2
votes
1answer
197 views

Altium buses between sheets on a flat design

I have a really big design to do and I'm having a rough time with buses. I have several doubts I hope someone can help me solve. Can I take a bus between sheets using an Off-Sheet Connector? For ...
0
votes
0answers
257 views

How to split a bus

I need a help with Altium Designer. I have a bus LED_DRIVE[20..1], and I would like to split this bus into 4 buses, named as ...
0
votes
2answers
87 views

How best to interface with this bus switch from an ESP32

I am wondering how to interface with this bus switch from a ESP32. I need to drive OE1 and OE2 LOW at 5v , see datasheet I know that I can only drive up to 3.3v from the ESP32 directly, so is there ...
-2
votes
3answers
97 views

Store more than 4 bit data on 8 bit bus

I don't have electrical background, but yesterday after watching some videos on youtube about old 8 bit computer, I have some question about how they work. 8 bit computer has 8 bit bus data which ...
0
votes
1answer
73 views

How to prevent SOIC8 clip from backfeeding

I'm trying to read the flash ROM using a SOIC8 clip, on board. I am horrible at surface mount soldering. Is there a way to use the clip on the board, without removing the chip, and not have the SOIC8 &...
5
votes
3answers
1k views

Looking for a device to “pass through” or “make high impedance” 8 bits based on one control bit

I need a thing (preferably a single IC) that has 8-bit input, 8-bit output and a control bit, with this behaviour: If the control bit is active, set output bits to the inputs (no need to actually ...
-3
votes
1answer
2k views

Multiple CAN bus devices broadcasting at the same time…possible conflict?

I've worked with CAN bus recently and started to wonder what would happen if multiple devices on a network suddenly happen to broadcast at the same time. I mean every device on the CAN-bus network ...
1
vote
1answer
283 views

Is there a fieldbus with more than 250 nodes per segment?

We plan to realize a sensor cable several 1000m long which has ideally every 1-2m a magnetic field sensor on a small 10x30mm platine with microprocessor/FPGA for DSP and I2C on chip communication. ...
0
votes
2answers
125 views

AT28C16 Interface Help

I pulled an AT28C16 from an old KVM switch and have managed to wire it up like so: A0-10 -> GND CE -> GND WE -> 5V OE -> GND VCC -> 5V GND -> GND I/O0-7 -> Floating. Plugged by hand to level meter ...
4
votes
4answers
699 views

Guidelines on PCB design with components only partially wired on PCB traces

There were a number of questions/answers here somewhat related to this question, but not exactly the same. I am developing an inverter with half bridge MOSFETs with high voltage and current over 100 ...
2
votes
1answer
665 views

Protocol for RS485 network?

I have to build a sensor network which communicates over a single RS485 bus. The network could have tens of nodes. The problem is that I have to control access to the shared bus and find a way to ...
0
votes
1answer
465 views

Sufficient Copper Thickness for 5V 4A

I'm trying to design a board that powers an MCU and a strip of Lights. The lights draw about 4A at 5V. In calculating the potential copper thickness of the PCB I'm a little lost. If i make the trace ...
0
votes
1answer
54 views

wired or bus troubleshooting

I have designed a photo-sensing array that consists of phototransistors (RPM075PTT86) and n-channel fets (see circuit below) duplicated 25 times. This is a very simple circuit that works OK, but I ...
2
votes
0answers
341 views

Bus interface for short distances, many device data exchange - CAN, RS485? + characteristic impedance and media capacitance

I ran into some troubles trying to design a wired bus which will connect in about 64 testing devices. My first choice of mind was CAN bus, known of it's reliability and low EMC interference. However, ...
0
votes
1answer
108 views

Memory chips, are the bits of a long word stored contiguously?

I am reading Structured Computer Organization, 6th edition by by Andrew S. Tanenbaum and Todd Austin. Chapter 3.3.5 talks about memory chips. I'm confused about the following paragraph, which relates ...
3
votes
3answers
1k views

Switching a CAN bus

I am designing the controller for a needle test station intended to do functional tests of a 20-PCB panel in a production line. The controller has to sequentially interface over CAN to 20 devices ...
2
votes
3answers
143 views

In VHDL, does having large bus input to component take extra resources?

I have a component that has a very large array signal in it (a couple kilobits) and I currently write and read to it in only one component. I have checked in Vivado if this uses too much resources, ...
0
votes
1answer
161 views

What is slave select signal on the APB bus for?

I am currently working on an APB BFM and I have a question regarding the bus protocol. I understand every slave on APB bus has its own unique address space, where its internal registers are mapped. ...
-1
votes
1answer
186 views

Why choose an 8bit over a 32bit MCU [closed]

With the recent Cortex-M rage, there seems to be a lot of 8bit bashing going around. I was wondering what specific use cases engineers encountered where 8bit MCUs were the preferred choice over 32bit,...