slviajero/tinybasic

What is ZX81 keyboard?

Closed this issue · 19 comments

Please tell me what is ZX81 keyboard in context of this interpreter? Is it a keyboard matrix wired like a real ZX81 keyboard? What are default pins for its connection? Can they be changed? Thanks.

Thanks. Are pins reassignable for nano, for example?

A really very reconfigurable intepreter. So after i SET output to display and input to keyboard, the "echo" of pressed keys will be also sent to display?

Therefore a standalone modern DIY Elektronika MK-85 like device, but 8-bit instead of 16, and with EEPROM instead of battery backup CMOS static RAM, is possible.

Compiler is even cooler, a similar feature exists in full version of Quick Basic (not Qbasic).

And also, when keyboard is not connected, and terminal is used, can i get "echo" of characters typed on terminal also sent to HD44780?

10 @i=1:@o=2:input a
20 print a
run
32768
When i run this program, line 10 starts asking for number, and i type 32768 on terminal, characters appear on terminal, not echoed to HD44780. Then i press enter, line 20 prints 32768 on HD44780.

Yes, because without it i cannot type anything in the emulator i use (real hardware is not assembled yet because of lack of free time; i already have a real nano and a display). Without picoserial enabled, the virtual terminal in emulator only outputs text, but not inputs it (on emulated nano).

Thanks, using outch made this work as expected. Set 3,1 and all i type appears on HD44780.

Closed

Even though issue is closed, thanks again. Tried this on real hardware, here is have i got it working:

  1. Using real nano also requires activating picoserial, otherwise it does not react to typing text (so this is not bug in emulator). Outch also works same way as on emulator.
  2. R/W line has to be grounded on real HD44780 unit i use; on emulator it does not matter.
  3. Maximum contrast is when corresponding line of the display is fully grounded by the potentiometer, do not know whether all such displays behave like this one.
  4. My display unit is 20x2, but i found that even this is configurable.
    Keyboard is not built yet.
    If being disconnected and then reconnected, nano (with CH340G) "jumps" either from /dev/ttyUSB0 to /dev/ttyUSB1, or back to /dev/ttyUSB0, depending on where it was previously. Baud rate is always 9600.

I use minicom as terminal program, this may be the cause.