Phone for my visually impaired grandma - Page 1
Forum section: electronics / projects

author: wkesther
author_rank: Newbie
timestamp: August 24, 2025, 07:50:11 pm
content: Hello everyone,I'm new here and have a project I'd like to get your opinion on. I want to build a user-friendly stationary phone for my grandmother who has poor eyesight and can't use a standard phone. This is my very first real embedded systems project, hence my knowledge is quite limited.How the phone should work:Calling someone:It should be possible to enter a phone number via a large keypad and to fast dial a saved contact through one of twelve buttons. When clicking either the button to call the entered number or one of the fast dial buttons, to confirm that a call has been started, a sound should be played through a speaker that's connected directly to the microcontroller.Receiveing a call:When someone is calling, one of two ringtones should be played through the speaker connected to the microcontroller. There should be two different ringtones to quickly determine if a saved contact or a unkown number is calling. A movement sensor should detect when my grandma is close to the telephone and if so start to play the correct audio file for example "Anna is calling" or "Unkown number is calling". I plan to save these audio files on a 32Mbit Flash-Storage module, because the microcontrollers flash is not big enough to save all of them.Key Components that I would currently consider:(Some are missing, because I either didn't find them yet or I already have them at home)Microcontroller:STM32F0F4P6 Development Board Link:https://shorturl.at/JLmiALTE Module:SIMCOM SIM7600G-H LTE Cat4 Link:https://shorturl.at/4FxGdFlash Storage Module:W25Q32 Flash-Storage module Link:https://shorturl.at/0K7knAntenna (2x):SMA LTE Antenna Link:https://shorturl.at/vz4c5SMA to U.F.L Pigtail (2x):SMA to U.F.L Pigtail Link:https://shorturl.at/C10cGIO Expansion Module:PCF8575 Module Expansion Link:https://tinyurl.com/yb77vk3dSpeaker (2x):Mini Speaker 8 Ohm Link:https://tinyurl.com/yc4e3vd3My Skills:I have a few years of experience in C/C++ and recently completed an introductory course on embedded systems in C.I have been learning embedded systems for about one month and am studying every day for atleast 6 hours. I want to pursue a career in embedded systems and am willing to study hard.My Questions for You:Do you think this project is realistic for someone with my skill level?Are there any obvious problems or challenges with combining these components that I might be overlooking?Should I use different components?Do you have any general advice for the implementation, especially regarding the communication between the STM32 and the LTE module?I'm open to all feedback and suggestions. Thanks in advance for your help!Best regards,Gabriel

author: xvr
author_rank: Frequent Contributor
timestamp: August 25, 2025, 12:02:19 pm
content: QuoteFirst suggestion: use an ESP32 module instead of an STM32. It includes up to 16MB of flash memory, which eliminates the need for a dedicated flash memory for audio.Next, you need an amplifier for the speaker. You can use a class D amplifier with an I2S input (for direct connection to the ESP32 without a DAC).Last, you forgot about the motion sensor in your specification.And maybe a motion sensor is not the best way to detect your grandmother, maybe a proximity sensor would be better.

author: tggzzz
author_rank: Super Contributor
timestamp: August 25, 2025, 12:24:55 pm
content: Your concept will take a long time to develop.You need to consider the mechanical form factor and enclosure, and whether it will be usable by your grandmother.Anything involving radio will be non-trivial.Your core requirements are not unique. Personally I would search for existing products designed for the elderly. You won't find a 100% match, but I'll bet you can find that 80% is usable - and being used within a week. If nothing else that would be cheap, fast, and enable you to verify what your grandmother finds useful.Good luck.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: August 26, 2025, 01:49:32 pm
content: Good Morning Wkesther, Here is just one of many that are available:https://www.amazon.com/Landline-Telephone-Visually-Impaired-Emergency/dp/B09G2LK6Z6/ref=sxin_16_pa_sp_search_thematic_sspa?adgrpid=1238050404563452&content-id=amzn1.sym.5a2f80d8-3686-499a-bbaa-70664bd0de70%3Aamzn1.sym.5a2f80d8-3686-499a-bbaa-70664bd0de70&cv_ct_cx=phone%2Bfor%2Bvisually%2Bimpaired&hvadid=77378317324169&hvbmt=be&hvdev=c&hvlocphy=105222&hvnetw=s&hvqmt=e&hvtargid=kwd-77378386826645%3Aloc-190&hydadcr=12420_13413856&keywords=phone%2Bfor%2Bvisually%2Bimpaired&mcid=b28b2adca2ab3455aa062087ce095a86&msclkid=6c00d1e630f41ecbf6a9b94b8a730428&pd_rd_i=B09G2LK6Z6&pd_rd_r=642acdee-14d4-423b-b116-ac19a4e4f901&pd_rd_w=1NE5z&pd_rd_wg=HFMms&pf_rd_p=5a2f80d8-3686-499a-bbaa-70664bd0de70&pf_rd_r=3EZBVBZH7BQ581WEPX1Z&qid=1756215971&sbo=RZvfv%2F%2FHxDF%2BO5021pAnSA%3D%3D&sr=1-3-6024b2a3-78e4-4fed-8fed-e1613be3bcce-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9zZWFyY2hfdGhlbWF0aWM&th=1

author: Simmed
author_rank: Frequent Contributor
timestamp: August 26, 2025, 03:55:20 pm
content: iirc adafruit seem to have some chatter on open phonesmaybe you can ask ladyada herself directly ?

author: artag
author_rank: Super Contributor
timestamp: August 26, 2025, 09:10:45 pm
content: In the UK, the RNIB (Royal National Institute for the Blind) sell a number of items especially useful for the blind and partially sighted. For examplehttps://shop.rnib.org.uk/search?options%5Bprefix%5D=last&page=1&q=telephoneSome of their devices, especially electronic magnifiers, seem insanely expensive. They're probably better made for the market (with consequently low manufacturing numbers) than general sales items though.You might find there's a similar organisation in your country that has something suitable. Not that I want to put you off developing the perfect solution, but as tggzzz says, it could take a while. And if it gets broken you have to start again ..

author: wilfred
author_rank: Super Contributor
timestamp: August 26, 2025, 11:55:20 pm
content: Vision Australia list a number of features to look for in a phone for vision impaired people on their website. Maybe it has some ideas for you. Although I think you want to consider a solution that will be easily replaceable in the event of a problem or loss. The recipient also once having become familiar with a solution will, depending on how difficult they find adapting to a new phone, want to continue with a minimum of effort.https://www.visionaustralia.org/technology-products/resources/using-technology/mobile-phones

author: wkesther
author_rank: Newbie
timestamp: August 27, 2025, 09:52:19 pm
content: Thank you all for your opinions and tipsI didn't realize that there are some phones on marketplaces like amazon suitable for visually impaired people. I will see what I can find and check if any meets my requirements.I am still relatively new to embedded systems, hence I don't have much experience and didn't think that this project is quite complex and that I might not have the required skills for it.I just thought that it would be a cool project to learn new important skills. I will try to build some easier projects first and maybe come back to this one some time later

author: Benta
author_rank: Super Contributor
timestamp: August 27, 2025, 10:51:52 pm
content: Try Doro,www.doro.comIt's a Swedish company that specializes in phones for elderly.Well designed and reasonably priced.As you're in Austria: Saturn and Media Markt carry them.

author: tggzzz
author_rank: Super Contributor
timestamp: August 27, 2025, 11:25:37 pm
content: Quote from: Benta on August 27, 2025, 10:51:52 pmDoro are one of the few manufacturers of mobilephoneswhich can be folded and put in your trouser pocket, without worrying about them being damaged by keys or by sitting on it, which lasts at least a week on standby, and which survive being dropped 7m onto concrete.

author: Benta
author_rank: Super Contributor
timestamp: August 27, 2025, 11:32:38 pm
content: My wife's Doro mobile lasts 10...15 days on a charge.

author: hfleming
author_rank: Regular Contributor
timestamp: August 28, 2025, 08:39:34 pm
content: All this advice is nice for your grandmom, (and I might be in that category as well needing to do only voice calls)…, but the biggest problem is with all the apps; you need an app to do your banking, and apps for doing this and that… how the hell does one do that?… or does one need to start carrying 10 magnifying glasses attached to you phone?

author: Benta
author_rank: Super Contributor
timestamp: August 28, 2025, 09:11:04 pm
content: Quote from: hfleming on August 28, 2025, 08:39:34 pmYou don't...unless you live in a society that mandates that everything has to be done with a smartphone, and no alternative method (the classic ones on paper) are allowed any more.Dunno about Norway, but Denmark comes to mind. Total digital dictatorship.