Personal development journal of Ben Ryves.
My original TI-83 Plus feels like it s on its last legs. I suspect there s some issue with the flash memory, and I ve already had to wipe its certificate page using the BootExec utility that exploits a buffer overflow in the link routines to get an operating system back on it. Even though it s working for now, I m somewhat wary of installing flash applications on it. Recently, however, someone…
Calculating the phase of the moon always struck me as a fun little program for a calculator, and with the current Artemis II mission it seemed like as good a time as any to look at a few example programs for this on a range of different calculators and pocket computers. Sharp PC-1211 I copied the following program from the book 119 Practical Programs for the TRS-80 Pocket Computer and it forms the…
The Sharp ZQ-700 Electronic Organizer, also sold as the Sharp OZ-700 Wizard, was a pretty interesting device. Its large 239×80 pixel resolution back-lit LCD and QWERTY keyboard made it a comfortable device to use, though the built-in programs are somewhat simplified from Sharp s more sophisticated earlier offerings; there s also no card slot for software expansion and the connectivity is…
I ve got a number of older computers that can print, but no printer for them. Quite often these computers require a serial printer, and so when a Serial 8056 printer popped up on eBay for around a tenner I picked it up. This is a thermal printer that takes fax paper rolls, so it seemed like a safe bet as far as consumables go (no need to source awkward cartridges, ink ribbons or spark paper) and…
Recent posts on here have taken a bit of a detour into Sharp Pocket Computer territory. When hunting down parts or accessories for them on eBay I ll occasionally be recommended other Sharp devices, such as their calculators or organisers, if an exact match for the thing I m actually hunting for can t be found. Calculators are indeed a useful tool, so I appreciate those recommendations, but…
I don t think I ve had a proper dose of "man-flu" since COVID and I haven t missed it at all. This journal entry has been written in a state of sleep deprivation whilst being tanked up on Lucozade and Lemsip (expiry date: March 2020) so hopefully it still makes some degree of sense. In my current state the most obvious project is to subject myself to the banshee howls of tape loading. I ve…
After my previous journal post about faster saving and loading of Sharp PC-1500 programs to and from tape I discovered that I was using a somewhat out-of-date version of Sharp Pocket Tools . The later version I upgraded to adds support for the "SuperTape" and "Quick-Tape" formats, and also includes copies of the PC-1500 programs for those formats. Both formats appear to support file names and…
After I ve typed a program into my Sharp PC-1500, I tend to save it to my PC for long-term storage using the CE-150 cassette interface. I use the same cassette interface to download programs shared by others over the Internet, and have written a previous post about resampling those shared wave files if you re struggling to load them. Loading a program this way is quicker than typing them in, but…
This is an extremely belated followup to a post from November last year , though one of the reasons for the delay was repeatedly being sent the wrong electronic components which ultimately led to the post from December . I ll try to explain as best I can... Towards the end of last year I bought myself a SmartBox, a computer control system that s based around a 65C02 CPU and that runs programs…
This is a quick post about problems I d been having loading tape cassette recordings from my PC to a Sharp PC-1500 Pocket Computer along with a potential solution for anyone having similar issues. Sharp PC-1500 Pocket Computer connected to the CE-150 Printer and Cassette Interface The Sharp PC-1500 is a small computer from the early 1980s that can run programs primarily written in BASIC. Programs…
I ve been having a tricky time buying LM35DZ analogue temperature sensors for a project recently. One pair of probes and a bag of loose components labelled LM35DZ turned out to be regular NPN transistors with a fake label on them, and another pair of probes ended up being DS18B20 digital temperature sensors. Whilst the DS18B20 temperature sensors were useless for the project I had in mind they…
My latest eBay purchase was influenced by a desire for some practical test/prototype equipment, a bit of nostalgia and a desire to learn something new. A lot of my projects involve some sort of microcontroller running some software that will take inputs, perform decisions on them, and produce outputs. Getting to that stage tends to involve quite a lot of "boilerplate" hardware and software setup,…
It s been quite a while since I posted about my Z80 Computer project. This is a home-made Z80 computer I built back in 2010 that features a 10MHz Z80 CPU with 64KB RAM that runs CP/M 3. It can drive an internal LCD, TV or VGA monitor at 320x240 (monochrome only) and unfortunately is a project I was never too happy with due to several compromises I had to make in its design – though at the…
When reading about the Cambridge Z88 computer and its available software I bumped into the occasional mention of Z-Tape by Wordmongers, a system that allowed you to back up files from your Z88 to a cassette recorder. I had wondered how this worked, assuming there some sort of external hardware to connect the cassette recorder to the Z88 (likely via its serial port). I d done some work on tape…
The previous release of the TI-83 Plus BootExec program relied on temporarily replacing TI s Silver Link driver with WinUSB if you wanted to use the Silver Link USB cable. I ve updated the program so it will try to use TI s driver if it s available, or WinUSB if not. This should help people who can t (or don t want to) temporarily replace TI s driver. The updated application can be downloaded, as…
This is a quick update to the TI-83 Plus BootExec program described in a previous journal entry . The program now supports the USB "Silver Link" cable (as well as the serial "Black Link" it previously supported) though to access the USB device you do need to temporarily replace TI s supplied driver with a generic WinUSB one which can be organised with Zadig . The updated application can be…
A few years ago I started running into problems with my TI-83 Plus graphical calculator. I was unable to install applications – it would keep locking up when "defragmenting". In the end I attempted to reinstall the operating system to see if that would cure matters, but that failed too and in the process left the calculator in a state where it wouldn t boot at all. Switching it on you d be…
The VDrive is a handy module for electronic projects that need to access files on a USB flash drive. It s based around a USB host microcontroller and comes preinstalled with some firmware that provides control over the drive with simple commands sent via a serial connection (UART or SPI). A few years ago I started putting together some code to connect the module to my Cambridge Z88 computer. All I…
One of the issues holding me back with my development of the Light Gun Commando project (aside from a lack of free time due to the day job) was running out of prototyping breadboards and the difficulty of swapping between different console adaptor boards for testing. Normally by this point I d have started soldering together more permanent prototypes on little circuit boards, but I ve been having…
After building a USB Guncon 2 adaptor for my Light Gun Commando project the Xbox seemed like it should be the next console to support as that also uses USB for its controllers. The xboxdevwiki seemed like a good starting point for information about its controller protocol. I wanted to be able to compare against real Xbox controllers too, so I bought an Xbox controller cable online and cut it in…