Bravo! I recently did a few KIM-1 episodes for my own channel you may wish to check. I thought you did a great job here but this could have been 3 episodes, at least for me! It was pretty fast, and I already knew most of what you were talkibg about, so you'd have to be pretty clever to pick it up on a first view! I appreciated the density of info, but for a broader audience you could have done how the Kim-1 decodes ands selected the right chip as it's own whole episode! Or I may just be slow 🙂 Subscribed!
Awesome Video !!! Not to fast at all. He perfectly explains how the KIM-1 uses Address lines A10-A12 and the 74145 to create select lines K0-K7 and what those lines are connected to, and how you can use those lines yourself. You are correct there was a lot of great information packed into this short video. The best thing about a video like this, is that you can always pause and re-wind, if you think you missed something... Which I do often ... 😃
Very cool!! The KIM-1 has always fascinated me. I would have been 12 y/o when it came out. Wish I could have gotten into computers at that age!! I was 18 when I bought my first computer, a TRS-80 Color Computer w/ 4K ram. Liked and subscribed -- keep the KIM-1 videos coming!
Great episode! Your visualizations of the decoding logic are amazing and also show just how the original KIM designers hit the right mix of easy expansion vs more advanced use of the memory map. And your explanation of the start and interrupt vectors makes so much sense, I'd always wondered how that worked. Thank you for all of your effort in making these episodes. Makes me want to do some breadboarding and try somethings out!
Really enjoying the series, hope you keep them coming! Great compliment to the Dave's Garage series, you both take slightly different approaches and they work well together!
@@commodorehistory Well, It has just become a little more popular... LOL!!! Add me to that list !!! Great video !!! Not to fast at all. You perfectly explained how to use K-0 thur K7. I have been reading a lot of KIM-1 books, and they never make it as clear, as you just did in this 17 minute video.
I had connected my KIM-1 to the old pc (equipped with p4 ht 530 processor) and I played chess with it using windows XP hyperterminal! really very cool!
I was able to preform the same expansion experiments using the standard Corsham Application board. Using the pinouts provided on JP5. The first expansion was easy, Just need to connect a jumper wire to K1 which is pin 3 on JP5, K2 is pin 2, K3 is pin 5 and K4 is pin 6. The second expansion over the 8K boundary, requires you to move the jumper on JP1 to Ext. This removes ground from the D input of the onboard 74145 decoder. To connect your breadboard's 74145 to K place a wire on Pin10 of JP5, and to connect the breadboard's 74145 to J, place a wire to pin 8 on JP5 . I was able to ohm these two connections out, to make sure that I was actually connecting to K and J using pins 10 and 8 on JP5. That way I was sure that I was wiring it up correctly. Everything worked out perfectly. Thank you for this extremely informative video !!!
I put a ton of effort into making this video knowing that it wasn't going to receive many views, but I hoped that someone might find it useful. Your comments made the effort worthwhile. Thank you so much, Jeff!
@@commodorehistory I only had one Extender Board, so I wanted to see if I could do this project using the regular Corsham application board. I picked up 3 - 27C64s and I got a bunch of- 2432s for about $5. I started working with a 28C16, that I had on hand. It worked for the most part, but when I would read past the small Butterfield program, I would not always see FFs. Whereas when I used the 27C64 it seemed a lot more stable. I had also loaded the Butterfield program in at $2000, $2400, $2800, $2C00, $3000 and I even stuck a #00 at $3FFF. I was thinking about sticking a group of 3 or 4 sets of header pins on a breadboard, so that I could have 2 or 3 ROMs or PIAs all running at the same time, using different address spaces. This truly was a great lesson for anyone looking to expand and or interface the KIM-1. Thank you !!!
@@commodorehistory I would love to see a good explanation of how the Keypad and 7 segment displays are constantly addressed while other parts of the program are running simultaneously.
Hi Evan, if you look at the MOS 6530 data sheet, you'll see that the chip select lines, rom select lines and a couple of the address lines were able to be mask programmed by MOS. The data sheet includes a diagram of what was possible. It allowed the 6530s to decode those parts of their address space separately from each other.
Absolutely. I initially did the 8k eprom circuit using a 74LS138 but switched to the 74LS145 to make the video so it would match what was shown in the user manual.
I am trying to bread board a possibly bad 6530-002 to my KIM-1. I have it all wired up. 6530 pin 3 (Phase 2) to Expansion pin U, 6530 pin 9 (R/W) to Expansion V, 6530 pin 16 (RES) to Expansion pin 7 and I have K4 from the Corsham application connector J5- pin 6, going to 6530 pin 4 (RS0) and J5- pin 4 (K2) going to 6530 pin 18 (CS1). My KIM-1 will not boot up with this bread board connected. The LEDs that I placed on the bread board on PA0 and PA1 do light up. I was wondering if you might be able to tell me what I am doing wrong? Do you think removing any of the control signals might resolve this issue?
@@commodorehistory I got my 6530-002 test breadboard working. I was missing the pull up resisters on K4 and K2 select lines. I found that the ROM would repeat 8 bytes of good commands there by replacing 8 bytes of good commands that should be there. It appears to do this throughout the entire ROM from $1000 where I have the ROM setup to $13FF. There may be a problem with the address A3. Either way, it looks like the 6530-002 may be bad. I have already had to replace the 6502 and if the 6530-002 is also bad, what do you think the chances are that the 6530-003 is still working??? I ordered the Corshame 6532 replacement board and hopefully it will be here soon. Although I wish someone would build a micro controller replacement maybe using a Arduno Nano, so that the single chip replacement does not cover up the whole board.
@@jeffnay6502 Great! Glad you got that working. I've personally had good luck with 6530s so you might be okay with the 6530-002 still. There is a fella working on an FPGA replacement for the 6530s that were in pinball machines and he expressed interest in extending his work to the 6530-002 and 6530-003.
Bravo! I recently did a few KIM-1 episodes for my own channel you may wish to check. I thought you did a great job here but this could have been 3 episodes, at least for me! It was pretty fast, and I already knew most of what you were talkibg about, so you'd have to be pretty clever to pick it up on a first view! I appreciated the density of info, but for a broader audience you could have done how the Kim-1 decodes ands selected the right chip as it's own whole episode! Or I may just be slow 🙂
Subscribed!
Hey thanks Dave!! I just mentioned you in my previous comment :)
I really appreciate you watching and value your feedback!
Awesome Video !!! Not to fast at all. He perfectly explains how the KIM-1 uses Address lines A10-A12 and the 74145 to create select lines K0-K7 and what those lines are connected to, and how you can use those lines yourself. You are correct there was a lot of great information packed into this short video. The best thing about a video like this, is that you can always pause and re-wind, if you think you missed something... Which I do often ... 😃
Very cool!! The KIM-1 has always fascinated me. I would have been 12 y/o when it came out. Wish I could have gotten into computers at that age!! I was 18 when I bought my first computer, a TRS-80 Color Computer w/ 4K ram. Liked and subscribed -- keep the KIM-1 videos coming!
Great episode! Your visualizations of the decoding logic are amazing and also show just how the original KIM designers hit the right mix of easy expansion vs more advanced use of the memory map. And your explanation of the start and interrupt vectors makes so much sense, I'd always wondered how that worked. Thank you for all of your effort in making these episodes. Makes me want to do some breadboarding and try somethings out!
Hi Mark! I really appreciate you taking the time to write such a positive comment. I'm super happy you enjoyed the video!
I got a sym-1, really helpful videos!
Congrats on the sym-1! They’re super fun devices. I really appreciate the kind feedback.
Me too
Really enjoying the series, hope you keep them coming! Great compliment to the Dave's Garage series, you both take slightly different approaches and they work well together!
I think my channel is a lot like Dave’s Garage except for being popular and successful :)
I thank you for watching and I thank you for the kind words!
@@commodorehistory Well, It has just become a little more popular... LOL!!! Add me to that list !!! Great video !!! Not to fast at all. You perfectly explained how to use K-0 thur K7. I have been reading a lot of KIM-1 books, and they never make it as clear, as you just did in this 17 minute video.
@@jeffnay6502 Jeff, this will be the best thing I read all day. Thank you so much for the kind words. Really, it made my day :)
Amazing, thanks for that clear explanation 👍
My pleasure! Thanks for the kind feedback!
I had connected my KIM-1 to the old pc (equipped with p4 ht 530 processor) and I played chess with it using windows XP hyperterminal! really very cool!
Fun times, indeed!
@@commodorehistory yes!
I was able to preform the same expansion experiments using the standard Corsham Application board. Using the pinouts provided on JP5.
The first expansion was easy, Just need to connect a jumper wire to K1 which is pin 3 on JP5, K2 is pin 2, K3 is pin 5 and K4 is pin 6.
The second expansion over the 8K boundary, requires you to move the jumper on JP1 to Ext. This removes ground from the D input of the onboard 74145 decoder. To connect your breadboard's 74145 to K place a wire on Pin10 of JP5, and to connect the breadboard's 74145 to J, place a wire to pin 8 on JP5 . I was able to ohm these two connections out, to make sure that I was actually connecting to K and J using pins 10 and 8 on JP5. That way I was sure that I was wiring it up correctly. Everything worked out perfectly.
Thank you for this extremely informative video !!!
I put a ton of effort into making this video knowing that it wasn't going to receive many views, but I hoped that someone might find it useful. Your comments made the effort worthwhile. Thank you so much, Jeff!
@@commodorehistory I only had one Extender Board, so I wanted to see if I could do this project using the regular Corsham application board. I picked up 3 - 27C64s and I got a bunch of- 2432s for about $5. I started working with a 28C16, that I had on hand. It worked for the most part, but when I would read past the small Butterfield program, I would not always see FFs. Whereas when I used the 27C64 it seemed a lot more stable. I had also loaded the Butterfield program in at $2000, $2400, $2800, $2C00, $3000 and I even stuck a #00 at $3FFF.
I was thinking about sticking a group of 3 or 4 sets of header pins on a breadboard, so that I could have 2 or 3 ROMs or PIAs all running at the same time, using different address spaces. This truly was a great lesson for anyone looking to expand and or interface the KIM-1. Thank you !!!
@@jeffnay6502 great to see you really running with it :)
@@commodorehistory I would love to see a good explanation of how the Keypad and 7 segment displays are constantly addressed while other parts of the program are running simultaneously.
@@jeffnay6502 I'll put that idea in the pipeline. Thanks for the suggestion!
How do the two RRIOTs determine which one is supposed to be reading or writing to RAM if they share the same CS line?
Hi Evan, if you look at the MOS 6530 data sheet, you'll see that the chip select lines, rom select lines and a couple of the address lines were able to be mask programmed by MOS. The data sheet includes a diagram of what was possible. It allowed the 6530s to decode those parts of their address space separately from each other.
Could you use a 74138 instead of a 74145 for address decoding?
Absolutely. I initially did the 8k eprom circuit using a 74LS138 but switched to the 74LS145 to make the video so it would match what was shown in the user manual.
I am trying to bread board a possibly bad 6530-002 to my KIM-1. I have it all wired up. 6530 pin 3 (Phase 2) to Expansion pin U, 6530 pin 9 (R/W) to Expansion V, 6530 pin 16 (RES) to Expansion pin 7 and I have K4 from the Corsham application connector J5- pin 6, going to 6530 pin 4 (RS0) and J5- pin 4 (K2) going to 6530 pin 18 (CS1).
My KIM-1 will not boot up with this bread board connected. The LEDs that I placed on the bread board on PA0 and PA1 do light up.
I was wondering if you might be able to tell me what I am doing wrong? Do you think removing any of the control signals might resolve this issue?
Goodness Jeff, I’d probably have to try connecting that up myself to see what’s going on. Off the top of my head I can’t even make a guess.
@@commodorehistory I got my 6530-002 test breadboard working. I was missing the pull up resisters on K4 and K2 select lines. I found that the ROM would repeat 8 bytes of good commands there by replacing 8 bytes of good commands that should be there. It appears to do this throughout the entire ROM from $1000 where I have the ROM setup to $13FF. There may be a problem with the address A3. Either way, it looks like the 6530-002 may be bad.
I have already had to replace the 6502 and if the 6530-002 is also bad, what do you think the chances are that the 6530-003 is still working??? I ordered the Corshame 6532 replacement board and hopefully it will be here soon. Although I wish someone would build a micro controller replacement maybe using a Arduno Nano, so that the single chip replacement does not cover up the whole board.
@@jeffnay6502 Great! Glad you got that working. I've personally had good luck with 6530s so you might be okay with the 6530-002 still. There is a fella working on an FPGA replacement for the 6530s that were in pinball machines and he expressed interest in extending his work to the 6530-002 and 6530-003.
@@commodorehistory I would like to know more about the specs of the chip that he will be using.
🤔🧠