MAx84xx Xxxx is a series of small MCS48 compatible microcontrollers with onboard mask ROM, Xxxx indicating the mask version. The code underneath it is just a date code. Also, from the board layout it can be deduced that the 75xxx pair are GPIB interface or line receiver/driver chips.
Congrats! I've got several of these since it's cheap enough to try your luck by buying multiple ones for ~$7 each. That and I wanted to help folks in Ukraine out (where I bought all of mine). I have the new displays as well. But I read over at HPMuseum that it's quite possibly the voltage converter that is what the problem is rather than the display. I also have the ROM module as well as a MK-61 and a MK-85. And somewhere on the net is an English version of the keyboard. Which is what led me to your site. :)
Very interesting and useful video. For some reason I have gotten the bug to do a little reminiscing and I purchased a couple of TI calculators on eBay/Mercari. I wish TI/HP/Casio/Sharp would make a modern “retro” LED calculator.
Thanks a lot for this video, it is still very useful even though it did take me a while to figure it out for my situation. I'm using a Chronodot RTC with the DS3231 chip and interfacing with my Bus Pirate 3.0a with the latest bootloader and firmware. The hardest part for me was understanding the proper way to address my Chronodot with the Bus Pirate interface, but this video helped a lot.
The cards without the black header are typically extra-use blanks that are not magnetic. The back side would be very shiny gray vs. the dullish dark gray/black of the magnetic cards. Typically, they were used for the TI-58C as it would remember your program when turned off. That way, you could write the labels on the card and slide it in for reference.
lol at the beginning about your friend is pretty much how my relationship with my mom was like when it came to money and things I wanted. Trust in my interests
Yeah! It was really amazing to see how his family worked. He had turned the finished basement into his room, and he basically had his own mini-apartment. He could have friends over whenever, lots of independence, as long as he maintained his grades and generally had good behaviour. I could go on for hours about all the cool stuff we did!
Been looking for a good approach/personal plan for eventually getting my ham license in Canada. I need to sit down with a study aid and keep playing around with a receiver. I'm aiming for the Basic with Honors. I've tried the online practice exams, and found out I need to study more.
Much much more PR needs to start happening before the gov't starts to think of taking over the crowded need for other essential communications. And Hams, one way or the other need to prove their worth in backup communications in time of disaster or civil defense as of days of old, and in time of war as trained skilled radio operators. In the past, the gov't gave the Hams what they called the "useless" bands like 80, 40, 20 meters etc, but Hams conquered them by working the world with them as well as creating different modes to operate llike SSB, teletype and circuit design. After World War 2, Hams almost lost it all, but to an ode to all the dead Ham telegraphers who died in the war in vain, the gov't reinstated it. Today the new software minded hams are working hard making more digital modes, put up untold satellites and such. Ham radio is one of the only licensed hobbies in the world and still going, especially in Europe who are wild of it. More PR, more and more and get your minds working on it. I could go on for hours and twice in my life, it actually saved my life with the calls to hams hundreds to a thousand miles away, while my cell phone went dead and out of range.
Thanks a lot for this! I'm trying to communicate with an IC from a RPi via I2C, problem is the IC uses a not-so-common convention of 16-bit mem addresses, & many bytes of data per command. More specifically, for a register read it wants: Start, 7 bit address, Read bit, Ack, Data [7:0], Ack, data [15:..=], not ack(?), Stop And for a write (i don't know why the python scripts for I2C commands don't seem to be doing anything - it maybe transmitting MSB and not LSB, as this IC requires): Start, 7 bit address, W bit, Ack, mem address [15:8], ACK, mem address [7:0], ack, Data [7:0], ack, data[15:..], Ack, Stop ^ having said that, most of the reads are many bytes at a time, so while the top write layout doesn't use repeated starts, i'm sure that's what it expects. Damn datasheet isn't as pretty as yours. Are you telling me this beautiful little IC should be able to communicate with the IC regardless of it's weird layout ? (i did just order version 3a, not 3.6 or 4 [hopefully shouldn't be a problem, eek])
+orbita1 I would highly recommend getting a USB logic analyzer, if you can afford one. It makes debugging problems like yours so much easier. I can't remember if the Bus Pirate supports 16-bit writes. You could easily whip up a microcontroller board to communicate with it, though. That would be dead simple with most modern microcontrollers. Let me know if you got it sorted out!
Dude, you are particularly gifted at teaching people complex subjects without them catching on that they just might be in over their heads! Good job man! How could anyone not subscribe?
+Ted Clapham Yes I did! Wow, you have the letters I wanted! I was going for VA3AMR or VE3AMR, both taken. Ended up with VA3XMR, which I really like. Been on the air for over two years now!
Im from Ottawa too! Im from Orleans. Im waiting for my bus pirate in the mail. Going to use it to program my fpga. Looke like quite a versatile little device
Man that ribbon cable tester is gold. I have been getting into repairs for hobbies. I enjoy cell phones, tablets, and nintendo handheld units like wii u, 3ds, and 2ds. The problems with these are the flat cables or ribbon cables? Not sure the actual technical names yet. The ribbon cable socket connectors have the latches and if they are not latched down properly then theres a short. You never know if its a new faulty screen you put in, or damage to the fcp socket connector. I learned if you use a piece of kapton tape as a shim it helps make them latch down better. IDK, as I said I'm a noob and an amatuer at best. I really respect you putting out all your hard earned knowledge out here. Thanks!
There is no hex value for the start command. The I2C bus has something called a "start condition", which tells the slave chip that we want to communicate with it. In Bus Pirate terminology, the start is represented by a square bracket; that notation is unique to the Bus Pirate.
It is glass reed-relays inside a coil (the green one). This is very much used in Philips devices. It is just a relay! nothing else. The very common problem with this is, that the glass tube breaks - and the reed relay cannot work. Just replace the reed relay (leave the coil alone...) and the instrument is working. You can buy the reed relays at RSonline or any other prof. shop. I have replaced a lot of them in Philips equipment. It works actually VERY well - just very sensitive to mechanical stress.
At 3:45: These 6-pinners placed in a straight row are opto-isolators. They are used to provide electrical isolation between the multimeter circuit and the GP-IB port.
SymphUK hey guys, would love to know what you think of my idea! I'm also known as MrAureliusR, this is my blog channel. I would love to know your experiences with electronic devices, if they helped Sarah's therapy, and if they were affordable or expensive.
The HP 54645D was given to me by a (somewhat) famous engineer, he wrote the book "Mastering the I2C Bus". I was really lucky! He doesn't usually send things like that halfway around the world for free!
Sure, when I post this video on my website I'll link to the schematic. Or better yet, maybe I'll do a video on how to build one! Yup, SparkFun tweezers, though eventually I'm going to replace them with better ones (though these are great value). Thanks for watching!
Congratulations on your Ham ticket! I wanted to thank you for sharing the Arduino software on Element 14. I have been working on building a CW tracking beacon for my little RC flying groups aircraft. Today I was able to massage your program to repeat my callsign as a beacon! I really appreciate your sharing your knowledge!
That SMD cap trick is nice, reminds me of the adhoc solution I recently did for an atmega µC. I didn't have small enough caps to do the XTAL1..2 connection to ground, so I - in my frustation - removed them completely, which actually worked, just by virtue of parasitic capacitance of the PCB......
Heya! I sent you an E-Mail, since I don't know how to verify that it is me who wrote that mail, my adress is johannes.kunkel (a) gmx {dot} net (let's hope this is bot-proof). Cheers!
