Prototypes

The different prototypes of Rookie drive

#1, The first prototype

Here we go!!, for rapid prototyping I used the rear bus output of the HX-10, 50-pin connector, to which I wired the address comparator and the ch376s, the eprom mounted on a cartridge plate in the top slot (pictured the cartridge with the eprom is out of the MSX, but it is actually in the slot)

My first tests were in from MSX Basic, simple things, detect the device, mount the unit, etc. From there, the assembler, the best way to learn ... This is my first project in assembler. I spent a few hours until it worked, at first I used a fixed disk image named HE.DSK, (for highway encounter), but it was boring, if I wanted to change games I had to connect the pendrive to the PC and change the image for another…

Unsatisfied at the moment, I soon got to work and create specific "CALL" commands to handle the device with ease. This time I was able to get some information about the glorious MSX.ORG page, in its wiki there is a section dedicated to the "CALL" command

So here is the list of "calls"

• createdisk  
• insertdisk(“image name”)
• eject
• usbfiles
• mount
• help

See details of features here

Then every time I turn on the computer I have to "insert" the disk by hand, so create the file "USBMSX.INI", which keeps the name of the last disk inserted, now when the computer is power on, it loads automatically (if you have autoexec) the last used image.

Of course, this is cool, but in the end it's tiring if you have to give CTRL + STOP, assuming BASIC is loaded, so I implemented the option to abort automatic insertion by pressing the ESC key when starting the computer.

At some point in the development I started to design with Kicad, so I have made some prototypes on PCB with pcbway, I am impatient to receive them ..

#2, The prototype of the impatient

Last weekend I can not wait any longer, the prototypes on PCB were taking longer than I had planned, so I decided to mount a prototype wired to start testing on other computers. The first prototype I did was not complete, I left the EPROM out of the prototype, since I could use a board I already had to mount the EPROM, thus saving me the 28 connections and I could test the circuit quickly.