Printing a base for my #RC2014

Overnight I've successfully compiled the sources for the #FUZIX operating system on my #Linux box and this morning, my #SC130 successfully booted into FUZIX ... yay!

https://www.fuzix.org/

#rc2014
#z80

My dual keypad module for the #RC2014.

This takes advantage on the Z80 IN instruction where the value of A is output on the upper 8 address lines. For keypad 1 I load either 1,2,4, or 8 into the A register, then read the value from the defined IO address. This puts a high across the row, and if a button is being pressed the row that button is in will also be high. In this case I am outputting the values of the column and row to the digital IO module to prove it is working.

+++ SYSOP NEWS +++ SYSOP NEWS +++

As you may remember, RC-BOX BBS - the world's first and (currently) only RC2014 based BBS - has been struggling with connectivity issues.

The good news: I have finally been able to successfully mitigate these.

Some background info: in October last year, I decided to do some maintenance on the system, updating my WiFi modem firmware and replacing the SC132 serial I/O module (using a 6.144 KHz crystal for a fixed 9600 bps) with its cousin, the SC110 serial I/O module which features a CTC chip so it can dynamically set any baud rate.

Turns out that while the module is techincally 100% okay, it sometimes locks up when being used with the BYE.COM program for CP/M.

I think this has to do with BYE.COM setting the CTC to the selected bps during initializiation (which happens after each hangup). For some reason, this often works but occasionally causes the SIO/2 to lock up.

Sometimes, without any reason, BYE.COM would drop into an +++ATH loop although no one was connected, not being able to actually perform the AT command.

It took me weeks to finally realize this, because I was so sure the problem originated from the Zimodem firmware and because the issue only showed up occasionally. It was very annyoing to debug.

So as a result of this finding, I've put the SC132 with the fixed 9600 bps back into the system. Since then, no more of these issues occurred.

As always, you can find all info on how to connect to RC-BOX BBS in my profile info.

P.S.: so now I think the problem originates from the BYE.COM code. But since everything is working properly again, I don't have the desire to dig into the BYE.ASM code any time in the future. There are other projects that I'd like to go on with first.

#rcbox
#bbs
#rc2014
#rc2014bbs
#retrocomputing
#newretro
#z80

I've written up how I got my ZX Printer compatible Alphacom 32 printer working on my #rc2014

https://www.robertprice.co.uk/robblog/using-a-zx-printer-on-an-rc2014/

Anyone having success running #FUZIX on the #RC2014 ?

#RC2014 Emulation for
#MiST and #SiDi #FPGA
available at
https://www.atari-forum.com/viewtopic.php?t=44842

I designed an address decoder for the #RC2014 that uses two 7400 ICs instead of a 74138. Reading any I/O port between 0x00-0x7f should return the state of the button in the least significant bit. 74125 /1OE should be low if RC2014 /IORQ and A7 are low and /M1 and /WR are high.

Edit: forgot the 100 nF capacitor.

This kit has the most sculptural soldering I’ve been called on to do!
#RC2014

Tonight’s the night!
#RC2014

Out there, in the worrying world of today is a little #Zilog #Z80 computer with a mere 64KB of #RAM and running the #1970s CP/M operating system.

This little machine is connected to the #intertubes and it's serving a #singleuser #bulletinboardsystem for you, the worrying souls of #yesteryears to visit.

Take a break from today, connect like it's 1985 - here on RC-BOX BBS, the world's first and (currently) only #rc2014 based bulletin board system in the world!

Check out the #alttext or my #profile info for information on how to connect.

#bbs
#rc2014bbs
#rcbox

I reworked my Z80 assembly language code last night and this is the result. My #RC2014 computer can now print to the Alphacom 32 printer.

This printer was originally designed for the ZX81 and ZX Spectrum and uses bit bashing to tell the printer whether to print a pixel or not as the print head moves along the paper.

I’m very pleased with this.

My #RC2014 is now talking to my Alphacom 32 (Sinclair ZX Printer compatible) printer. I’ve not got the software right, but at least it’s printing something, and the printer is starting and stopping correctly.

Could not resist this! #rc2014

I designed a new version of my keypad adapter for the RC2014. The second circuit diagram is more detailed and mimics the layout of my breadboard.

Parts: four 10k resistors, 100nF capacitor, four diodes (e.g. 1N4448), 7495, 74125, 74138, matrix keypad with 4*4 buttons.

To read one row of the keypad:
1) Write 1, 2, 4 or 8 to any I/O port between 0x00-0x1f.
2) Read a byte from any of those I/O ports. The 4 least significant bits correspond to buttons on that keypad row.
#RC2014

Did you know that the #RC2014 Mini II Picasso can be assembled in just 52 seconds?

https://youtu.be/0uKWB_SsgDk

Whilst it is still before midday in some time-zones, I just want to share the good news that the new #RC2014 Mini II Picasso has gone on display at the Tate Modern art gallery!

You can get your very own piece of art from #z80kits right now https://z80kits.com/shop/rc2014-mini-ii-picasso/

Remember, you can't spell UART without ART