Forum - Recent Threads

What are your thoughts on double-density or hybrid connector formats- is it worth the complexity?

Greta_Reilly — Wed, 20 Aug 2025 21:14:37 GMT

As Amphenol Communications Solutions continues to expand its portfolio with double-density and hybrid connector offerings, do you see this shaping design choices and connector strategies in your applications?

RE: What are your thoughts on double-density or hybrid connector formats- is it worth the complexity?

colporteur — Wed, 27 Aug 2025 14:14:49 GMT

I did a search of Amphenol double-density and hybrid connector products. They bring a tear to my eye. They make for extremely difficult repairs. Replacement becomes the first option:( Care to provide a few specific products you like to evaluate?

What do you feel separates one A2L sensor from the other and what drives your design decision?

Julianne — Mon, 28 Jul 2025 19:36:03 GMT

Understanding that all A2L sensors are designed within the guidelines of UL 60335-2-40

Telaire T3400 Series Refrigerant Gas Sensors are designed to meet the needs of OEM manufacturers for high-performance A2L refrigerant leak detection and mitigation. These fully calibrated and packaged sensors are UL/ETL recognized components, enabling efficient system integration and certification to UL60335-2-40 standards.

How do you choose the right connector for high-speed applications?

CalvinTerence — Tue, 01 Jul 2025 04:53:17 GMT

With so many factors to consider - signal integrity, mating cycles, pitch, PCB vs cable routing, EMI shielding etc. Selecting the right connector can make or break a design.

What technical specs matter the most to you when selecting a connector?

How do you handle signal integrity challenges in high-speed backplane applications?

Greta_Reilly — Mon, 16 Jun 2025 13:19:38 GMT

How do you handle signal integrity challenges in high-speed backplane applications?

Which industrial automation trends are driving your connector selection in harsh environments?

Greta_Reilly — Tue, 03 Jun 2025 20:03:17 GMT

Which industrial automation trends are driving your connector selection in harsh environments?

RE: Which industrial automation trends are driving your connector selection in harsh environments?

dougw — Wed, 04 Jun 2025 02:15:23 GMT

Although automation is not the overriding focus, our products are expanding the capabilities of wearable electronics which see lots of shock and vibration in addition to extreme environmental conditions of moisture and temperature. And of course wearable connectors also need to be small, light and sturdy.

Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

ralphjy — Thu, 13 Apr 2023 21:38:09 GMT

The MRJ598001 Rugged RJ45 Jack is a panel mount assembly that is rated IP67, but I can't find a mating solution (connector or cable assembly) that would allow me to use it in a waterproof application. Can you provide me links to possible solutions.

Thanks,

Ralph

RE: Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

KelleyNall — Fri, 14 Apr 2023 15:35:06 GMT

Great! I did get a response from my contact - see below:

The MRJR series is designed to work with any RJ plug connector and is IP rated to prevent fluid ingress from passing through the mating cavity into the box. If the customer wants to protect the mating connection as well the attached protective boot assembly can be purchased. Part number is MUSBRAHD2321SK, attached is the link to the data sheet and product drawing.

P-MUSBR-AHD2-XX1XX-REVE - Sheet (amphenol-cs.com)

IP67 Boot Style Hood (amphenol-cs.com)

RE: Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

ralphjy — Fri, 14 Apr 2023 15:08:22 GMT

Thanks for the response. I will check with Nadeem.

Ralph

RE: Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

KelleyNall — Fri, 14 Apr 2023 15:00:50 GMT

Hi Ralph- please email Nadeem (Product Manager for the rugged mod jack line) from Amphenol to answer your question. nadeemk@amphenolcanada.com

Thanks!

Kelley Nall

RE: Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

ralphjy — Thu, 13 Apr 2023 22:18:33 GMT

Thanks. I was hoping that an Amphenol person might be monitoring this forum and could tell me if they had implemented a solution. I think I might have found their solution, so I'll switch over to the challenge forum (I probably should have started there)...

RE: Waterproof mating connector for MRJ598001 Rugged RJ45 Jack

shabaz — Thu, 13 Apr 2023 22:12:02 GMT

Hi Ralph,

Only the socket is rugged/waterproof. the cable would be a standard one. I think they are expecting the cable to be protected just by any moulded boot on the end and perhaps just mounted in a enclosure with a lip or something to prevent direct rain falling on it.

Sometimes the socket is mounted very recessed for instance, and then the enclosure may have some other means to provide a bit more protection to the cable where it enters the recess. In other words, this connector would need the enclosure designer to also implement some of that extra stuff. But the connector will still seal to the enclosure, so that the enclosure is still IP67.

How does Tx Only Serial Communication Actually Work?

Sean_Miller — Sat, 28 Dec 2019 21:15:08 GMT

I have a YDLidar X2 device that I found doesn't actually have a Rx line. By design, it has no wire on the connector and doesn't expect any commands to be sent to it. It just continuously transfers out its packets representing the state of its sensor.

I hadn't realized it until today that every project I've ever done with serial was by me sending a command and awaiting a response. It was so intuitive, I never thought how the bits where banging.

So, my question is - does such a device that has no Rx line somehow fill a buffer and pause until bytes are read by the user or is it just pulsing and not caring what's happening on the line?

If it does pause, what gives the flag that it is good to continue?

If it does not pause, how in the world does the receiving device know how to sync up with the bits streaming?

Or, does serial protocol actually use the Tx line alone as a bus to talk back to coordinate the transfer of data from the transferring device? If not, I would think it would create nothing but garbage if it started listening at a random time.

Thanks,

Sean

RE: How does Tx Only Serial Communication Actually Work?

Sean_Miller — Sun, 29 Dec 2019 04:34:34 GMT

Thanks so much! It finally clicked for me.

I have trouble thinking in such small fractions of a second, but if I envision that chart scaled out to minutes, there is no doubt I could write a routine to poll the signal in all kinds of ways and feel confident I captured the timing of the highs and lows correct. It's just that computers now for decades can perform such a function at freaky fast speeds with confidence.

As you state, the width of each expected pulse gives room for error when you target the middle. Any rhythm or speed differences between the two device clocks will be reset after the 8th bit of each byte preventing drift over time. It's really genius and so darn simple at the same time. I love it.

Thanks so much for helping me get over the hump on this one.

-Sean

RE: How does Tx Only Serial Communication Actually Work?

neuromodulator — Sun, 29 Dec 2019 04:15:15 GMT

Because you must know the timing (Actually there are timing algorithms too, but thats more complex). I recently implemented an UART receiver on my FPGA, so if you understand Verilog and have an FPGA I could share it with you. Usually algorithsm work kinda like this.

you run a clock at say 16 times the speed of 1 bit duration. So for instance if you plan to receive a signal of say 2400 bps, you need to sample at a rate of 38400. Here is an example of a signal 8N1 (8 data bit, no parity bit and 1 stop bit).

So you once you detect a falling edge, you will wait enough time to sample right in the middle of the bit1 and then bit2, and so on. If you want the receiver to be more robust you may want to sample multiple times every bit in order to avoid that transients corrupt your data. In the best case scenario a transient would just corrupt a single or very few samples from the bit. So for instance if you sample 5 times every bit, its likely that if a transient occured, it would flip just 1 or very few samples out of the 5 in total. The transmitter and receiver could use different clocks, and there could be a mismatch in their timing, but that shouldn't be an issue if you continuosly resync the clock.

RE: How to do a Double Byte XOR Checksum?

neuromodulator — Sun, 29 Dec 2019 03:56:45 GMT

I'm glade you got it working. I've never used a LIDAR but can imagine they are quite fun.

How to do a Double Byte XOR Checksum?

Sean_Miller — Sat, 28 Dec 2019 17:24:05 GMT

I have a data packet that states its data validation (check code) is verified by a double byte XOR. I've Googled for a tutorial and came up empty. I've tried to solve the puzzle in Excel to never get a match to serial data I captured with Putty. I could use a tip on how the algorithm to apply.

The packet description is below. Starting at position 8, the two byte CS item contains the check code and states it uses a double-byte XOR to verify the current data packet. I've tried adding up all bytes starting at Si in series which equates to a two byte value. I XOR it against the CS value I've assed to be xC4AD, but that didn't resolve to 0.

Should I be XORing blocks of 2 bytes and comparing to the CS value?

[View:/resized-image/__size/491x83/__key/communityserver-discussions-components-files/62/contentimage_5F00_126595.png:491:83]

[View:/resized-image/__size/571x231/__key/communityserver-discussions-components-files/62/contentimage_5F00_126596.png:571:231]

Example packet:

AA 55 00 28 85 AE 9D 0C AD C4 00 00 00 00 00 00 32 00 00 2A 12 59 12 00 00 00 00 A6 1F E5 1F 8D 1F 6D 1F 0A 17 7D 17 62 55 09 1D B1 10 31 10 4D 10 7A 0F 61 0F 5D 0F 21 0F 19 0F 31 0F 49 0F 8D 0F 4E 6D 6D 1D 82 0D 84 0D 00 00 AE 1A 9D 1A 89 1A

RE: How does Tx Only Serial Communication Actually Work?

Sean_Miller — Sun, 29 Dec 2019 02:30:30 GMT

So, when it falls low and signals the start bit, I picture that it will then a series of highs and lows. Without a clock line to index each bit, how does the 8 bits of the byte about to transmit get received without getting confused when you have two Highs in a row or two Lows in a row?

Thanks,

Sean

RE: How to do a Double Byte XOR Checksum?

Sean_Miller — Sun, 29 Dec 2019 02:17:20 GMT

Yep...had a bug in that I was not XORing the full bounds of the sample data array in my ported Arduino code. It's now 100% as you said! The "Good Data" in my post a few minutes ago must have occurred when the Last Angle's (LSA) most significant byte was zero so it didn't affect the checksum.

All that is happening here within .001 seconds absolutely boggles my mind and inspires me that the world should become an amazing place for our kids.

Arduino code is below. One could readily expand this to decipher object distance at given angles around the YDLIDAR or log a point map for importing into software to establish a geometry from a point cloud. This approach is much, much leaner than their SDK and good for the likes of Arduino and the Azure Sphere Starter Kit.

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 212, 74 New Checksum: 212, 74

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 59, 83 New Checksum: 59, 83

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 3, 15 New Checksum: 3, 15

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 84, 101 New Checksum: 84, 101

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 218, 107 New Checksum: 218, 107

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 97, 95 New Checksum: 97, 95

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 133, 244 New Checksum: 133, 244

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 129, 92 New Checksum: 129, 92

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 171, 26 New Checksum: 171, 26

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 5, 155 New Checksum: 5, 155

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 90, 72 New Checksum: 90, 72

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 158, 81 New Checksum: 158, 81

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 169, 15 New Checksum: 169, 15

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 37, 96 New Checksum: 37, 96

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 72, 107 New Checksum: 72, 107

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 139, 98 New Checksum: 139, 98

20:06:07.391 -> Good: Samples Sent: 40 Checksum: 66, 185 New Checksum: 66, 185

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 205, 70 New Checksum: 205, 70

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 157, 30 New Checksum: 157, 30

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 92, 236 New Checksum: 92, 236

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 250, 106 New Checksum: 250, 106

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 93, 85 New Checksum: 93, 85

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 51, 15 New Checksum: 51, 15

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 214, 104 New Checksum: 214, 104

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 129, 106 New Checksum: 129, 106

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 20, 95 New Checksum: 20, 95

20:06:07.423 -> Good: Samples Sent: 40 Checksum: 237, 251 New Checksum: 237, 251

20:06:07.435 -> Good: Samples Sent: 40 Checksum: 108, 93 New Checksum: 108, 93

20:06:07.469 -> Good: Samples Sent: 40 Checksum: 53, 74 New Checksum: 53, 74

20:06:07.469 -> Good: Samples Sent: 40 Checksum: 140, 149 New Checksum: 140, 149

20:06:07.469 -> Good: Samples Sent: 40 Checksum: 178, 117 New Checksum: 178, 117

bool first_byte_received;
bool second_byte_received;
int incomingByte;


void setup() {
  Serial.begin(115200);
  first_byte_received=false;
  second_byte_received=false;
}


void loop() {
  // Poll for our expected 3 bytes that reflect the packet header.
  if (Serial.available()) {      // If anything comes in Serial (USB),
    incomingByte=Serial.read();
    //Serial.println(incomingByte);
    if (!first_byte_received) {
      if (incomingByte==170) first_byte_received=true;
    }
    else if(!second_byte_received) {
      if (incomingByte==85) {
        second_byte_received=true;
      }
      else
      {
        first_byte_received=false;
      }
    }
    else
    {
      if (incomingByte==0) {
        first_byte_received=false;
        second_byte_received=false;
        ReceivePacket();
      }
      else
      {
        first_byte_received=false;
        second_byte_received=false;
      }
    }
  }
}


void ReceivePacket() {
  int samples_sent, starting_angle_LSB, starting_angle_MSB, end_angle_LSB, end_angle_MSB;
  int check_code_LSB, check_code_MSB;
  int left_column[50], right_column[50];
  int sample_bytes[100];
  
  while (!Serial.available());
  samples_sent=Serial.read();


  // Expect no more than 40 really, but just in case, just punt if more than 50.
  if (samples_sent>50) {    
    return;
  }
  
  while (!Serial.available());
  starting_angle_LSB=Serial.read();
  while (!Serial.available());
  starting_angle_MSB=Serial.read();
  while (!Serial.available());
  end_angle_LSB=Serial.read();
  while (!Serial.available());
  end_angle_MSB=Serial.read();
  while (!Serial.available());
  check_code_LSB=Serial.read();
  while (!Serial.available());
  check_code_MSB=Serial.read();
  
  for (int ii=0;ii<((2*samples_sent)); ii++) 
  {
    while (!Serial.available());  
    sample_bytes[ii]=Serial.read();
  }
  
  // Perform checksum
  int left_checksum=0;
  int right_checksum=0;
  
  left_checksum=left_checksum ^ 170;
  right_checksum=right_checksum ^ 85;
  
  left_checksum=left_checksum ^ starting_angle_LSB;
  right_checksum=right_checksum ^ starting_angle_MSB;


  for (int ii=0; ii<((samples_sent*2)-1); ii+=2)
  {
    left_checksum=left_checksum ^ sample_bytes[ii];
    right_checksum=right_checksum ^ sample_bytes[ii+1];
  }
  
  left_checksum=left_checksum ^ 0;
  right_checksum=right_checksum ^ samples_sent; 


  left_checksum=left_checksum ^ end_angle_LSB;
  right_checksum=right_checksum ^ end_angle_MSB;
  
  String assessment="Bad";
  if (left_checksum==check_code_LSB&&right_checksum==check_code_MSB) assessment="Good";
  Serial.println(assessment + ":  Samples Sent:  " + String(samples_sent) + " Checksum: " + String(check_code_LSB) + ", " + String(check_code_MSB) + "  New Checksum: " + String(left_checksum) + ", " + String(right_checksum) );
  while
(Serial.available()){Serial.read();}

}

RE: How to do a Double Byte XOR Checksum?

Sean_Miller — Sun, 29 Dec 2019 02:03:55 GMT

I ported the checksum code posted above to the Arduino and wrote a loop to catch the start of the packet and then parse the entire packet.

Since I never have been one to compile successfully on the first try, I found the checksum comes in handy to catch my bugs and performance issues. Here you see after every 11th packet read, I finally get a good check. Of course at these crazy speeds, there is more than enough good data to snag, but I still need to perfect the Arduino code to do better - or address any data transfer problems I might be having from my cables.

-Sean

19:38:56.966 -> Samples Sent: 40 Checksum: 226, 72 New Checksum: 155, 85

19:38:56.966 -> Samples Sent: 40 Checksum: 187, 108 New Checksum: 22, 106

19:38:56.966 -> Samples Sent: 40 Checksum: 144, 2 New Checksum: 57, 11

19:38:56.966 -> Samples Sent: 40 Checksum: 42, 109 New Checksum: 37, 109

19:38:56.966 -> Samples Sent: 40 Checksum: 202, 76 New Checksum: 202, 76

19:38:56.966 -> Samples Sent: 40 Checksum: 12, 118 New Checksum: 212, 107

19:38:56.966 -> Samples Sent: 40 Checksum: 227, 144 New Checksum: 114, 132

19:38:56.966 -> Samples Sent: 40 Checksum: 137, 64 New Checksum: 235, 93

19:38:56.966 -> Samples Sent: 40 Checksum: 184, 121 New Checksum: 0, 122

19:38:56.966 -> Samples Sent: 40 Checksum: 121, 214 New Checksum: 201, 216

19:38:56.966 -> Samples Sent: 40 Checksum: 111, 127 New Checksum: 78, 98

19:38:56.966 -> Samples Sent: 40 Checksum: 140, 74 New Checksum: 197, 87

19:38:56.966 -> Samples Sent: 40 Checksum: 98, 108 New Checksum: 36, 106

19:38:56.998 -> Samples Sent: 40 Checksum: 217, 15 New Checksum: 116, 10

19:38:56.998 -> Samples Sent: 40 Checksum: 2, 108 New Checksum: 1, 109

19:38:56.998 -> Samples Sent: 40 Checksum: 69, 77 New Checksum: 69, 77

19:38:56.998 -> Samples Sent: 40 Checksum: 208, 118 New Checksum: 148, 107

19:38:56.998 -> Samples Sent: 40 Checksum: 210, 147 New Checksum: 187, 131

19:38:56.998 -> Samples Sent: 40 Checksum: 176, 91 New Checksum: 219, 109

19:38:56.998 -> Samples Sent: 40 Checksum: 229, 105 New Checksum: 217, 97

19:38:57.023 -> Samples Sent: 40 Checksum: 179, 209 New Checksum: 143, 217

19:38:57.023 -> Samples Sent: 40 Checksum: 146, 113 New Checksum: 128, 111

19:38:57.057 -> Samples Sent: 40 Checksum: 184, 72 New Checksum: 57, 84

19:38:57.057 -> Samples Sent: 40 Checksum: 24, 111 New Checksum: 102, 106

19:38:57.057 -> Samples Sent: 40 Checksum: 92, 3 New Checksum: 92, 10

19:38:57.090 -> Samples Sent: 40 Checksum: 239, 111 New Checksum: 108, 109

19:38:57.090 -> Samples Sent: 40 Checksum: 70, 77 New Checksum: 70, 77

19:38:57.090 -> Samples Sent: 40 Checksum: 150, 64 New Checksum: 76, 93

19:38:57.090 -> Samples Sent: 40 Checksum: 96, 174 New Checksum: 207, 128

19:38:57.123 -> Samples Sent: 40 Checksum: 66, 125 New Checksum: 137, 112

19:38:57.123 -> Samples Sent: 40 Checksum: 14, 0 New Checksum: 234, 102

19:38:57.123 -> Samples Sent: 40 Checksum: 159, 201 New Checksum: 147, 151

19:38:57.156 -> Samples Sent: 40 Checksum: 192, 64 New Checksum: 114, 90

19:38:57.156 -> Samples Sent: 40 Checksum: 8, 72 New Checksum: 25, 85

19:38:57.156 -> Samples Sent: 40 Checksum: 201, 117 New Checksum: 204, 112

19:38:57.189 -> Samples Sent: 40 Checksum: 161, 14 New Checksum: 115, 10

19:38:57.189 -> Samples Sent: 40 Checksum: 36, 75 New Checksum: 56, 75

19:38:57.189 -> Samples Sent: 40 Checksum: 255, 77 New Checksum: 255, 77

19:38:57.189 -> Samples Sent: 40 Checksum: 86, 70 New Checksum: 250, 88

RE: How does Tx Only Serial Communication Actually Work?

neuromodulator — Sun, 29 Dec 2019 00:24:42 GMT

The simple approach for 8n1 is to wait for 10 or more time units that line is high. That will tell you that the line is idle. At that moment you wait for falling edge (start bit) wich will tell you that byte transmission will begin.

RE: How to do a Double Byte XOR Checksum?

neuromodulator — Sun, 29 Dec 2019 00:19:25 GMT

Leave the lidar scanning for a while and letme know if you find a checksum error. I suspect thst you wont

RE: How does Tx Only Serial Communication Actually Work?

Sean_Miller — Sat, 28 Dec 2019 23:37:27 GMT

In I2C, you have the clock line to keep the beat and compare against. With serial, how does the receiver know a zero since the edge already fell?

-Sean

RE: How does Tx Only Serial Communication Actually Work?

neuromodulator — Sat, 28 Dec 2019 22:48:55 GMT

When the line is in idle its at 1, when it begins transmitting goes to 0 (start bit). The falling edge indicates the beginning of a byte transmission. So unless the transmitter is sending data at full speed, its straightforward to synch to the transmitter, as the line cant stay high for 10 or more time units, unless its in idle.