There are many tutorials on the topic out there, did you try to do a bit of research?
first hit:
Hello i try to research about this topic and i try many blood pressure device we are working for digital not manually blood pressure
And what you expecting from the forum?
The link that @J-M-L provided is for digital.
Hi I’m working on an academic project and I’m wondering if anyone here has experience extracting data from blood-pressure monitors. I’m interested in lawful, research-grade approaches and any pointers to tools, datasheets, or tutorials would be really helpful.
Yes, I mean a digital device. We don’t want to extract data by manually pumping the cuff; we’re looking for legitimate ways to read stored measurements from the blood-pressure unit with proper permission.
Your title states you want to make a blood pressure sensor not read data from a medical unit.
Maybe you should change the title
Thankyou, I'm fixing it now
The question needs an additional details... at least the name/model of the medical device where you are reading from.
I have neither seen nor owned a manual sphygmomanometer in years. They inflate by pump, and the readout is displayed on an LCD including my home machine. My home machine 'talks' to my iPhone via Bluetooth so maybe you can capture that signal for your purpose. An Arduino or esp32 with bluetooth capability (make sure it is the right kind of bluetooth) could easily replace the display that came with the sphygmomanometer although I have no idea why.
Here we still need to clarify what the OP understands by "legitimate ways" ?
Ask the manufacturer for permission and data sheets, rather than a hobbyist forum.
Can you provide more description of 'academic project'?
Why do you mention 'lawful'?
No, you mean an automatic device. A manual BP cuff uses a rubber bulb to inflate the cuff. An automatic BP cuff uses a DC powered air pump to inflate the cuff.
A manual BP cuff requires training as the person using it has to know when to stop inflating (when you can't feel the radial pulse anymore, plus a couple extra pumps, which is roughly the systolic BP marker before deflating the cuff and listening via stethoscope for the actual systolic BP reading).
An analog BP cuff is one with an analog gauge and should be used in conjunction with a stethoscope (but doesn't have to, although by palp will not allow you to obtain the diastolic BP). A digital BP cuff has a digital readout and does not require a stethoscope.
You could use the EEPROM in an Arduino to store the last BP reading and compare it to the current one, if it is desirable to you to store the last reading that persists beyond cycling the power to the device.