Choppy connection from Virtual Machine to FTDI 232R
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}
Context
I have been tasked with getting a DOS program to run on more modern hardware. This program uses a serial COM port to communicate with a target device at a relatively low BAUD rate (4800 is typical).
So far I have used VirtualBox on a Windows machine to create a FreeDOS VM and have acquired a FTDI TTL-232R cable and a virtual COM port driver for that cable.
Problem
This setup kind of works actually. The software is able to communicate with the target device, but an oscilloscope shows that two or three bytes will be sent, and then up to ten milliseconds will elapse before another cluster of bytes are sent. This causes the target device to time out before it has received the full message.
Troubleshooting
The Windows computer I'm using actually still has a DB9 port. If I use that instead of the FTDI cable, the software works smoothly. This leads me to believe that the problem is not being caused by FreeDOS.
To test the FTDI cable, I wrote a short Python script on the Windows machine (using pyserial) to communicate with the target device using the virtual COM port. This also worked smoothly.
I've also read through The relevant documentation. I've tried adjusting driver settings with no affect. It also seems unlikely that the driver is the source of the problem given that the python script works fine.
Help!
If anyone has ideas on how to troubleshoot this further or recognizes the problem at hand, some advice would be greatly appreciated!
windows virtualbox serial-port freedos ftdi
add a comment |
Context
I have been tasked with getting a DOS program to run on more modern hardware. This program uses a serial COM port to communicate with a target device at a relatively low BAUD rate (4800 is typical).
So far I have used VirtualBox on a Windows machine to create a FreeDOS VM and have acquired a FTDI TTL-232R cable and a virtual COM port driver for that cable.
Problem
This setup kind of works actually. The software is able to communicate with the target device, but an oscilloscope shows that two or three bytes will be sent, and then up to ten milliseconds will elapse before another cluster of bytes are sent. This causes the target device to time out before it has received the full message.
Troubleshooting
The Windows computer I'm using actually still has a DB9 port. If I use that instead of the FTDI cable, the software works smoothly. This leads me to believe that the problem is not being caused by FreeDOS.
To test the FTDI cable, I wrote a short Python script on the Windows machine (using pyserial) to communicate with the target device using the virtual COM port. This also worked smoothly.
I've also read through The relevant documentation. I've tried adjusting driver settings with no affect. It also seems unlikely that the driver is the source of the problem given that the python script works fine.
Help!
If anyone has ideas on how to troubleshoot this further or recognizes the problem at hand, some advice would be greatly appreciated!
windows virtualbox serial-port freedos ftdi
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05
add a comment |
Context
I have been tasked with getting a DOS program to run on more modern hardware. This program uses a serial COM port to communicate with a target device at a relatively low BAUD rate (4800 is typical).
So far I have used VirtualBox on a Windows machine to create a FreeDOS VM and have acquired a FTDI TTL-232R cable and a virtual COM port driver for that cable.
Problem
This setup kind of works actually. The software is able to communicate with the target device, but an oscilloscope shows that two or three bytes will be sent, and then up to ten milliseconds will elapse before another cluster of bytes are sent. This causes the target device to time out before it has received the full message.
Troubleshooting
The Windows computer I'm using actually still has a DB9 port. If I use that instead of the FTDI cable, the software works smoothly. This leads me to believe that the problem is not being caused by FreeDOS.
To test the FTDI cable, I wrote a short Python script on the Windows machine (using pyserial) to communicate with the target device using the virtual COM port. This also worked smoothly.
I've also read through The relevant documentation. I've tried adjusting driver settings with no affect. It also seems unlikely that the driver is the source of the problem given that the python script works fine.
Help!
If anyone has ideas on how to troubleshoot this further or recognizes the problem at hand, some advice would be greatly appreciated!
windows virtualbox serial-port freedos ftdi
Context
I have been tasked with getting a DOS program to run on more modern hardware. This program uses a serial COM port to communicate with a target device at a relatively low BAUD rate (4800 is typical).
So far I have used VirtualBox on a Windows machine to create a FreeDOS VM and have acquired a FTDI TTL-232R cable and a virtual COM port driver for that cable.
Problem
This setup kind of works actually. The software is able to communicate with the target device, but an oscilloscope shows that two or three bytes will be sent, and then up to ten milliseconds will elapse before another cluster of bytes are sent. This causes the target device to time out before it has received the full message.
Troubleshooting
The Windows computer I'm using actually still has a DB9 port. If I use that instead of the FTDI cable, the software works smoothly. This leads me to believe that the problem is not being caused by FreeDOS.
To test the FTDI cable, I wrote a short Python script on the Windows machine (using pyserial) to communicate with the target device using the virtual COM port. This also worked smoothly.
I've also read through The relevant documentation. I've tried adjusting driver settings with no affect. It also seems unlikely that the driver is the source of the problem given that the python script works fine.
Help!
If anyone has ideas on how to troubleshoot this further or recognizes the problem at hand, some advice would be greatly appreciated!
windows virtualbox serial-port freedos ftdi
windows virtualbox serial-port freedos ftdi
asked Mar 5 at 18:57
Andrew BlomenbergAndrew Blomenberg
1
1
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05
add a comment |
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05
add a comment |
1 Answer
1
active
oldest
votes
Been there, done that.
Most likely you have bought a "fake" FTDI USB-to-Serial. Those "sort of work" but do funny things.
Get a real FTDI (or even better: A PL2303) and things will smooth out.
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "3"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fsuperuser.com%2fquestions%2f1411569%2fchoppy-connection-from-virtual-machine-to-ftdi-232r%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Been there, done that.
Most likely you have bought a "fake" FTDI USB-to-Serial. Those "sort of work" but do funny things.
Get a real FTDI (or even better: A PL2303) and things will smooth out.
add a comment |
Been there, done that.
Most likely you have bought a "fake" FTDI USB-to-Serial. Those "sort of work" but do funny things.
Get a real FTDI (or even better: A PL2303) and things will smooth out.
add a comment |
Been there, done that.
Most likely you have bought a "fake" FTDI USB-to-Serial. Those "sort of work" but do funny things.
Get a real FTDI (or even better: A PL2303) and things will smooth out.
Been there, done that.
Most likely you have bought a "fake" FTDI USB-to-Serial. Those "sort of work" but do funny things.
Get a real FTDI (or even better: A PL2303) and things will smooth out.
edited Mar 7 at 19:20
answered Mar 5 at 19:48
Eugen RieckEugen Rieck
11.3k22429
11.3k22429
add a comment |
add a comment |
Thanks for contributing an answer to Super User!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fsuperuser.com%2fquestions%2f1411569%2fchoppy-connection-from-virtual-machine-to-ftdi-232r%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
You could test if this is an issue with the VM by testing this in DOSBox, which also provides Serial Port binding.
– Worthwelle
Mar 5 at 19:05