Comments on: 6502 breadboard computer part 8 – next steps http://www.suppertime.co.uk/blogmywiki/2021/04/6502-breadboard-computer-part-8-next-steps/ reading, writing, coding, making Tue, 24 Oct 2023 13:43:21 +0000 hourly 1 http://wordpress.org/?v=3.1 By: John Helliwell http://www.suppertime.co.uk/blogmywiki/2021/04/6502-breadboard-computer-part-8-next-steps/#comment-100788 John Helliwell Tue, 08 Jun 2021 18:07:27 +0000 http://www.suppertime.co.uk/blogmywiki/?p=3831#comment-100788 Hi Giles. I had a look at the Vt-69, I'm not sure whether it exists or not. I haven't made any progress on a memory-mapped display yet but I have a small screen attached now. I am using an old Raspberry PI and a 3.5" LCD screen which runs terminal emulation. It gives me VT100 style escape codes so I have colour and character based screen formatting. <a href="http://kingdonjon.blogspot.com/" rel="nofollow"> Hi Giles.
I had a look at the Vt-69, I’m not sure whether it exists or not. I haven’t made any progress on a memory-mapped display yet but I have a small screen attached now. I am using an old Raspberry PI and a 3.5″ LCD screen which runs terminal emulation. It gives me VT100 style escape codes so I have colour and character based screen formatting.

]]> By: blogmywiki http://www.suppertime.co.uk/blogmywiki/2021/04/6502-breadboard-computer-part-8-next-steps/#comment-100594 blogmywiki Thu, 20 May 2021 07:43:13 +0000 http://www.suppertime.co.uk/blogmywiki/?p=3831#comment-100594 Hi John, Your project sounds fantastic! I'm going to enjoy exploring it this weekend and start a shopping list as mouser.com... lots of ideas there. Serial interface is intriguing. I'm not keen on anything that requires a 'real' computer to connect but if I got my hands on a modern dumb terminal like a VT-69 that could change things, although I *really* like the idea of building a machine with its own keyboard and multi-line LCD display. best wishes Giles Hi John,
Your project sounds fantastic! I’m going to enjoy exploring it this weekend and start a shopping list as mouser.com… lots of ideas there. Serial interface is intriguing. I’m not keen on anything that requires a ‘real’ computer to connect but if I got my hands on a modern dumb terminal like a VT-69 that could change things, although I *really* like the idea of building a machine with its own keyboard and multi-line LCD display.
best wishes
Giles

]]> By: John Helliwell http://www.suppertime.co.uk/blogmywiki/2021/04/6502-breadboard-computer-part-8-next-steps/#comment-100593 John Helliwell Wed, 19 May 2021 20:31:30 +0000 http://www.suppertime.co.uk/blogmywiki/?p=3831#comment-100593 Hi Giles, I have greatly enjoyed having a look at your 6502 blog. Ben Eater is inspirational and I have been busy building his 6502 breadboard kit and developing my own add-ons this year. I particularly like your work with a keypad, it provides a simple interface with lots of ability to communicate - so I may add one to my system. When I finished Ben's set of hardware videos (I will do the BCD and interrupts videos later) I thought about improvements I wanted to make. My assembly programming is very dubious requiring many iterations before programs work so my first task was to avoid the need to remove/replace the EEPROM each time I wanted to write a program. The 6502 breadboard project has nearly everything you need to program the EEPROM in situ and as you know it is very similar to the RAM. With the address and data signals already there you just need a little bit of logic for the write operations. Ben has a video "Build an Arduino EEPROM programmer" which gives you an idea of what is required - although I didn't use shift registers. Simple programs can be coded by hand in an Arduino sketch then downloaded to the EEPROM, starting at 0x8000. As my programs became larger I found it easier to write a little C program to convert the output from vasm assembler to a data file which the Arduino sketch can send to the EEPROM. Life suddenly became a whole lot easier. I also really needed to get some sort of terminal i/o. I saw on 6502.org that W65C51 ACIA chips provide a simple serial interface. Googling existing projects to do this, I (like you) came across Dirk Grappendorf's website and was able to use his code to control the ACIA. This provided me with full terminal I/O using putty on my PC. Life got a whole lot better for me at that point. Since then I have been spending some time practicing some simple assembler and I need to get a monitor working so that I can load a variety of programs and check what is happening on the machine - if it goes well I may even call it a memory resident operating system! Like you I am keen to try using some of Steve Wozniaks code. Thanks for you interesting blog, I hope I have provided some ideas for "what you should do next" Hi Giles, I have greatly enjoyed having a look at your 6502 blog. Ben Eater is inspirational and I have been busy building his 6502 breadboard kit and developing my own add-ons this year.
I particularly like your work with a keypad, it provides a simple interface with lots of ability to communicate – so I may add one to my system.
When I finished Ben’s set of hardware videos (I will do the BCD and interrupts videos later) I thought about improvements I wanted to make.
My assembly programming is very dubious requiring many iterations before programs work so my first task was to avoid the need to remove/replace the EEPROM each time I wanted to write a program.
The 6502 breadboard project has nearly everything you need to program the EEPROM in situ and as you know it is very similar to the RAM. With the address and data signals already there you just need a little bit of logic for the write operations. Ben has a video “Build an Arduino EEPROM programmer” which gives you an idea of what is required – although I didn’t use shift registers.
Simple programs can be coded by hand in an Arduino sketch then downloaded to the EEPROM, starting at 0×8000. As my programs became larger I found it easier to write a little C program to convert the output from vasm assembler to a data file which the Arduino sketch can send to the EEPROM. Life suddenly became a whole lot easier.

I also really needed to get some sort of terminal i/o. I saw on 6502.org that W65C51 ACIA chips provide a simple serial interface. Googling existing projects to do this, I (like you) came across Dirk Grappendorf’s website and was able to use his code to control the ACIA. This provided me with full terminal I/O using putty on my PC. Life got a whole lot better for me at that point.

Since then I have been spending some time practicing some simple assembler and I need to get a monitor working so that I can load a variety of programs and check what is happening on the machine – if it goes well I may even call it a memory resident operating system! Like you I am keen to try using some of Steve Wozniaks code.

Thanks for you interesting blog, I hope I have provided some ideas for “what you should do next”

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