Gender changers are often build this way with the ports upside down, cause it is much more easy to connect the two plugs inside. You just need nine straight traces on the PCB inside, no weird crossing things. By the way: A Sub D 9 to nine single dupont sockets is one of my most used adapters. Self build and very useful, all wires are numbered and color coded.
I think this is the most amazing video on the CB2 micro you have done up to now. Certainly the way a thinking engineer gets his hands on debugging and finding the solution to problems. I really enjoyed that one and I can't wait to see more. Congratulations!!
Thank you for such an informative video. Whilst the CB2 is interesting, it was your deeper dive into the serial comms that caught my attention most! Especially as it is relevant to many tech gadgets. This video is now in my “watch again” list 😊
I used a lot of MAX232 back in the late 80s and early 90s. I had those tantalum capacitors on stock. The ICs I didn’t keep in stock because DC to DC conveyors were expensive. Like 30 euros of today’s money. But most of the 8051 microcontrollers that I build interfaced with my PC. I was aware of RS232 -12V to +12V of an early age (12), because I asked my dad : “why is there a negative voltage in computers? What is it used for?!” He explained RS232 to me and balanced lines. And told me about the DEC terminals he used at work. Not knowing that 10 years later, I’d be soldering 100s of these connectors and configure Arnet and Digiboards (multi serial cards for a PC) to connect terminals to our applications written in MUMPS.
Dude!!!! I am sure you are reading this because this still a small channel, n_n I wish the best. Your content is amazing, I always thought technology was like math you start simple with fractions multiplications and division but they are the building blocks of complex equations. i know my basic electronics (transistors, resistances, oscillators, capacitors...) but watching this is like learning to add and substract but with components. whish in turn make micro-components more understandable. It is amazing to think computer communicate trough electrical wave patterns. but this is getting long winded. n_n so just thank you for all this info.
Of course I'm reading the comments 😃 Glad you're enjoying it. And I agree, electronics is like many other things, made out of building blocks you slowly put in place 👍
@8:00 the reason why the RS232 stuff isn't working is because the board designer is INVERTING the serial port which is wrong. use a max232 and you'll be correct, also, the RS232 spec is +/-12 volts not 5 volts. TTL Spec is +/- 5 volts
@@NoelsRetroLab well on the other side of the coint.. as long as the swing is > +/- 3 volts (IIRC - been a while) then most max232/233 converters will see it properly. just have to be careful not to put a +/- 12 volt REAL rs232 connection on a TTL uart like directly on a micro controller.x
FTDI TTL serial UART cables can generally be reprogrammed to reverse the polarity of the I/O pins using their program MProg available on their website. This may only work with cables with genuine FTDI chips rather than the clones.
Very interesting video. I love when people use oscilloscopes when explaining things and troubleshooting. Like they say, a picture is worth a thousand words.
Great video. I agree with your comments about more ram and better sound. Personally I would get rid of the Scart connector too, not only as they are huge and old, but those connectors are pretty expensive too for what they are. On my version the keyboard connector would be USB, as would be the serial port, ideally with support for flash drives. :-)
Thanks. Yes, I can see that. Scart is nice because the signal is super simple. If you do HDMI you probably need some kind of chip to drive that, right? Not sure on the details. Same with a USB connector, that might involve some other kind of chip. So I see where they were coming from, but I would have at least added a USB port for communication.
Or a chip like FT232 or MCP2221A to do USB to UART. MCP2221A is specially good because it comes in a DIP package and only requieres 3 caps and the usb port to get going. It even supports USB to I2C!
So you make sure that the USB-to-serial interface includes that chip, or are you saying that you just build it yourself? Any trouble getting the PC to talk to that device?
@@NoelsRetroLab build it. MCP221A Its a real simple circuit, works on a breadboard even. No drivers hassle from microchip. Only 2 USD on mouser for single qty DIP package.
@@NoelsRetroLab hah! I was just typing about the MAX232. I would be a little pcb sitting on between this CB2 and the RS232 of the USB to serial. But you can also get a little FTDI shield and have a nice 5V serial, and you probably have those for programming atmel’s. (Nevermind I continued watching and you got out the FTDI :) )
Good to know! I wonder why it didn't work. High-speed transmission doesn't seem to be a priority for the CB2 project, which is understandable, but still, since it's an option in the menu, I'm surprised it didn't work.
@@NoelsRetroLab In fact, I opt for adding even lower serial speeds, either embedded into chipbasic or by altering the CBterm program (everything is in assembly). Such low speeds will support RTTY, a mode that HAM radio people use, right out of the box :)
I can't believe you are so knowledgeable about retro computers in general, but knew so little about RS-232 and didn't have the proper equipment already to interace with it. Great video anyway.
Yeah, that was the first time I was interfacing with RS232 at that level. Most of the computers I deal with don't use it or I didn't have the need for it at the time. So it was a learning experience (which is really fun for me).
@@NoelsRetroLabI thought most of our generation learnt RS-232 from early multiplayer games where two computers would be connected via serial, copying files over serial between computers, modems and bulletin board systems, and the occasional serial port based hardware hack. We all have different experiences I suppose. Thanks again for the awesome videos!
Thanks, educational video. eBay is full of cheap and dodgy USB to RS232 adaptors. I had the same problem updating the software on my Telescope controller when I got onto the support forum there were heaps of other people suffering the same issue. The answer is to get an FTDI type RS232 adaptor. iBuffalo being a common brand.
I'm old enough to know that RS232 often means much more than 5 V ! But since I'm a software guy, I didn't know that it was from minus something to plus something. I noticed that your second USB/UART adapter is based on an FTDI chip : good, I like these ones because they present a serial number. When working under Linux, you can set some udev rules to create an alias, for example /dev/mySpecificSerialDevice --> /dev/ttyUSBx. Whatever the order of detection, the USB port it's pluged in, etc, you'll be able to identify your device based on this FDTI serial number and always use the same /dev/mySpecificSerialDevice. With the CB2, you should be able to use Cutecom for example. When working under Windows, well, it's plug and pray ... It may work as intended for weeks or months, and, one day, for no reason at all, Windows will decide that the adapter you never unplugged will change from COM3 to COM12 ... Windows is magic ! Be careful though, there has been some knock of, and few years ago, FTDI released drivers that killed the fake chips ! Pffff, smoke ... But I never witnessed such retaliation myself ... That being said, I'm surprised it didn't worked at 38400 bps. I've been using few FTDI to debug STM32 FWs at 460800 without any problem ! Did you changed the settings in Teraterm ? (perhaps I missed it in the video)
Wow, that's a throwback and a half. Hyper Terminal! Software that somehow escaped from windows98. :-D It brings back so many memories, and they are all bad. It belongs in the Recycle Bin.
No need to open the serial converted, you can use the continuity test of your multi meter to check the wiring. For a 1-to-1 connection you would need to cross all lines, so rotating the connector 180 degrees from one side to the other helps. The serial connector choice on the CB2 seems wrong, it should be a female connector on the board, replacing the connector would be useful. Usually serial communication with micro controllers works at TTL levels. Putty is an excellent terminal program with lots of features
Atmel/Microchip make an ATMEGA 1284P which is a dip-40 and has 16k of static ram and 128k of flash, so in principle a CB2 could be made with 4 times the memory, and plenty or room for an upgraded editor and interpreter.. I don't know off the top of my head if it is pin compatible, although I imagine it is. There is certainly scope for this device, I always think its incredible what can be done with microcontrollers, and considering the ATMEGA is not the newest device I love the simplicity and cheapness. I think it would probably not be too hard to put in an emulation of a sound chip like the AY-3-8910 or SN76489. I have programmed ATMEGAs to generate polyphonic multi waveform sound in the past, although it does use a lot of processing power so something simpler would be better. Then with some support in the basic for it, it would make a fun platform to allow people to make their own "chiptunes". You also get to enjoy the experience of messing with RS-232 which is very retro computing!
thank you for posting. as i remember, i think one of the comments on your cb2 earlier video suggested a usb-ftdi adapter [similar to the little red pcb gizmo you used] instead of the usb2rs232 dongle you started w/. also, while waiting for the fem2fem db9 gender changer, would a few fem2fem dupont jumpers have worked ? perhaps the rs232 pins are too large in dia for the dupont jumpers. please take care & stay safe.
Maybe it's not in the spirit of retro computing, but there are some amazingly powerful microcontrollers around a similar price point to the ATmega644 these days - picking a random one, the STM32F730 has a 32-bit ARM Cortex M7 capable of 200MHz, 276KB of SRAM, an FPU and a boatload of peripherals for just 11 USD in single quantity! Amazing how cheap computing power is these days, but there's still something satisfying about getting every last bit of performance out of an 8-bit CPU
Delay is, probably, configured in hyperterminal, because of no flow control, to prevent remote system from skiping symbols on overflow. And you, usually, don't need +5V from remote system for powering USB-to-UART adapter. It usualy takes enough power from USB, so only RX, TX and GND needed.
The AVR-MCU make use of the Harvard architecture and separates program (AVR: flash) from data memory (AVR: RAM, EEPROM). The 80s home computers are make with von Neumann architecture, where program and data shares the same memory. This means for CB2 it's not possible to place executable machine code into ram and execute it. That's a big differrnt to Z80, 6502 etc.
How many ways the IT industry managed to screw up something as simple a serial port... And yeah, lot of the cheap "usb to serial" adapters are junk.:( Great detective job as usual!
Yeah, seriously. The quality of some of those adaptors is abysmal. And then you don't know exactly where the problem is: the driver, the hardware, the way the computer handles things...
The screw up is that that particular adapter doesn't send data at remotely the correct speed when configured at 1200 or 2400 bps. Other than that, it would be probably work fine, even with the 0-5V range.
You are not actually limited to 95 lines of total code like the video mentions. You can use the CALL function to combine programs (total 8 programs) for a total of 760 lines of BASIC code. And if you write your programs with functions, you can recall them at any time ;)
@@freeeflyer It's a matter of available memory. BUT please read the comments. You can use the CALL function to combine more than one program positions. This will lead you to a total of 760 lines of basic code, if you use all 8 program positions. So there is no actual 100 line limitation, but 760 lines limitation :) This does not count the functions that can be re-used many times within your code :)
RS232's specs are +15v to -15v differential. While +3v and -3v are the absolute minimum ratings (in the spec), the 5v differential is getting awfully close to that minimum. With this low voltage, the cable length will have to be small, and may be susceptible to errors. A MAX232 chip would have been better (with a proper voltage differential), but I doubt they are made now days.
I do not know if you seen it, but there is a simple Vic20 emulator for the Arduino Uno. It does not support graphics or sound but it does emulate the CBM BASIC 2.0 environment well through a terminal. I forget where I seen it but you should be able to find it quickly under google.
I hadn't seen it but that sounds like a cool project. I'm kind of surprised it doesn't do graphics emulation though. I guess the Arduino can't handle it.
@@NoelsRetroLab - I found one that does its own video but no true graphics more. I'm sure there are better ones than this one. Should be simple for you. Due to the small footprint the Arduino Uno/Mini/Nano, the Emulated Vic20 has about 1.25K RAM. create.arduino.cc/projecthub/janost/the-nano-vic-20-e37b39
USB to serial cables never quite work well, and sometimes they are 100% rubbish. There's usually issues with timing, voltage levels, or both. You have both issues. Any surprise why my main workstation has four COM ports?
I have that same green cable for about 20 years and it is a headache, the cable uses a chip intended for HID (cheaper) and not a UART chip, windows detects it wrong, it thinks it is a human interface device and the driver in many cases is poorly programmed. I still use it (but at my own risk) with a linux laptop, I open the corresponding / dev and I have no problems, I use it to connect devices such as smart card readers, industrial equipment, etc. The truth is that for usb to RS232 the best thing is a cable that contains the FT232 chip as said above unless you have a lot of experience in the field. And beware the FT232 is a very counterfeit chip.
Hi Noel, I've got my CB2 Microcomputer up and running. BUT, I can't get hyperterminal to even start. It keeps asking for area codes. I don't know what it means. Can you please help?
Urgh. Yes, that's "normal" as far as I can tell. Seriously! I type anything and then move on. But seriously, drop that and go get TeraTerm instead. Much better and it doesn't have that weird delay.
12:18 I’m seeing you suffering to debug the PC output and I’m like JUST GET A INDUSTRIAL COMPUTER WITH SERIAL PORTS Just in case you decide to try an industrial motherboard for the serial, I recommend you the Asrock IBM150 It has 3 external COM ports 2 internal COM ports, and you can adjust the mode and voltage if I’m not wrong
Using different program slots is the same as the Casio PB-110. I've got to get one of these. I think I have sent him an email. (I just don't understand how they work. LOL).
Linux needs/uses "drivers" (kernel modules quite often) too, it just happens to include a trillion generic ones. This "cable" isn't a straight-through cable. It's a USB UART conversion chip (CH340), inside a cable. Yes, Linux does include the CH340 driver, as well as the common FTDI one, and probably others.
That USB-serial adapter is so bad, I would have tried to get my money back. I don't use serial very much, but when I do, I like to use the ports on the motherboard of my desktop or the base station of an old laptop.
Oh, regarding your desire for more memory during program execution time, please see this extension that you can easily build cb2.qrp.gr/extensions/#4._External_EEPROM_expansion
Gender changers are often build this way with the ports upside down, cause it is much more easy to connect the two plugs inside. You just need nine straight traces on the PCB inside, no weird crossing things.
By the way: A Sub D 9 to nine single dupont sockets is one of my most used adapters. Self build and very useful, all wires are numbered and color coded.
I think this is the most amazing video on the CB2 micro you have done up to now. Certainly the way a thinking engineer gets his hands on debugging and finding the solution to problems. I really enjoyed that one and I can't wait to see more. Congratulations!!
Thank you for such an informative video. Whilst the CB2 is interesting, it was your deeper dive into the serial comms that caught my attention most! Especially as it is relevant to many tech gadgets. This video is now in my “watch again” list 😊
LOL, when I saw that "CH-340" chipset identifier on the USB cable, I knew exactly what mistake you had made.
I used a lot of MAX232 back in the late 80s and early 90s. I had those tantalum capacitors on stock. The ICs I didn’t keep in stock because DC to DC conveyors were expensive. Like 30 euros of today’s money. But most of the 8051 microcontrollers that I build interfaced with my PC.
I was aware of RS232 -12V to +12V of an early age (12), because I asked my dad : “why is there a negative voltage in computers? What is it used for?!”
He explained RS232 to me and balanced lines. And told me about the DEC terminals he used at work. Not knowing that 10 years later, I’d be soldering 100s of these connectors and configure Arnet and Digiboards (multi serial cards for a PC) to connect terminals to our applications written in MUMPS.
Very enjoyable and informative to watch. People debug problems in different ways; nice to hear your thought process. Thanks!
Dude!!!! I am sure you are reading this because this still a small channel, n_n I wish the best.
Your content is amazing, I always thought technology was like math you start simple with fractions multiplications and division but they are the building blocks of complex equations. i know my basic electronics (transistors, resistances, oscillators, capacitors...) but watching this is like learning to add and substract but with components. whish in turn make micro-components more understandable.
It is amazing to think computer communicate trough electrical wave patterns. but this is getting long winded. n_n so just thank you for all this info.
Of course I'm reading the comments 😃 Glad you're enjoying it. And I agree, electronics is like many other things, made out of building blocks you slowly put in place 👍
@8:00 the reason why the RS232 stuff isn't working is because the board designer is INVERTING the serial port which is wrong. use a max232 and you'll be correct, also, the RS232 spec is +/-12 volts not 5 volts. TTL Spec is +/- 5 volts
That's right about the RS232. Did I say +-5V? Oops, yeah it should be +-12V. Good catch!
@@NoelsRetroLab well on the other side of the coint.. as long as the swing is > +/- 3 volts (IIRC - been a while) then most max232/233 converters will see it properly. just have to be careful not to put a +/- 12 volt REAL rs232 connection on a TTL uart like directly on a micro controller.x
FTDI TTL serial UART cables can generally be reprogrammed to reverse the polarity of the I/O pins using their program MProg available on their website. This may only work with cables with genuine FTDI chips rather than the clones.
No, there is no inversion anywhere. It is pure RS-232 "compatible". The voltage levels are a bit low, but still within the standard.
Very interesting video. I love when people use oscilloscopes when explaining things and troubleshooting. Like they say, a picture is worth a thousand words.
This looks like a great little device and a fun project. It's also very much aligned to my basic soldering skills... I'll order one.
I'll review another small device like this soon, way more powerful, but also harder to solder. So this one is probably a great starting point.
Great video. I agree with your comments about more ram and better sound. Personally I would get rid of the Scart connector too, not only as they are huge and old, but those connectors are pretty expensive too for what they are. On my version the keyboard connector would be USB, as would be the serial port, ideally with support for flash drives. :-)
Thanks. Yes, I can see that. Scart is nice because the signal is super simple. If you do HDMI you probably need some kind of chip to drive that, right? Not sure on the details. Same with a USB connector, that might involve some other kind of chip. So I see where they were coming from, but I would have at least added a USB port for communication.
As a rule i always use a MAX232 whenever i intend to use RS232 on a micro. Less headache that way.
Or a chip like FT232 or MCP2221A to do USB to UART. MCP2221A is specially good because it comes in a DIP package and only requieres 3 caps and the usb port to get going. It even supports USB to I2C!
So you make sure that the USB-to-serial interface includes that chip, or are you saying that you just build it yourself? Any trouble getting the PC to talk to that device?
@@NoelsRetroLab build it. MCP221A Its a real simple circuit, works on a breadboard even. No drivers hassle from microchip. Only 2 USD on mouser for single qty DIP package.
@@NoelsRetroLab hah! I was just typing about the MAX232. I would be a little pcb sitting on between this CB2 and the RS232 of the USB to serial. But you can also get a little FTDI shield and have a nice 5V serial, and you probably have those for programming atmel’s.
(Nevermind I continued watching and you got out the FTDI :) )
Your channel is really well made. It should have more subscribers.
Hi Noel. I have the same FTDI module as you were using at the end. These can handle 115200 baud easily so it isn't that at fault transmitting at 3400.
Good to know! I wonder why it didn't work. High-speed transmission doesn't seem to be a priority for the CB2 project, which is understandable, but still, since it's an option in the menu, I'm surprised it didn't work.
@@NoelsRetroLab In fact, I opt for adding even lower serial speeds, either embedded into chipbasic or by altering the CBterm program (everything is in assembly). Such low speeds will support RTTY, a mode that HAM radio people use, right out of the box :)
I can't believe you are so knowledgeable about retro computers in general, but knew so little about RS-232 and didn't have the proper equipment already to interace with it. Great video anyway.
Yeah, that was the first time I was interfacing with RS232 at that level. Most of the computers I deal with don't use it or I didn't have the need for it at the time. So it was a learning experience (which is really fun for me).
@@NoelsRetroLabI thought most of our generation learnt RS-232 from early multiplayer games where two computers would be connected via serial, copying files over serial between computers, modems and bulletin board systems, and the occasional serial port based hardware hack. We all have different experiences I suppose. Thanks again for the awesome videos!
You have far too little subscribers for such incredible content... loved this.
good job as always Noel, you are such a professional !
Thanks, educational video.
eBay is full of cheap and dodgy USB to RS232 adaptors. I had the same problem updating the software on my Telescope controller when I got onto the support forum there were heaps of other people suffering the same issue. The answer is to get an FTDI type RS232 adaptor. iBuffalo being a common brand.
I'm old enough to know that RS232 often means much more than 5 V ! But since I'm a software guy, I didn't know that it was from minus something to plus something.
I noticed that your second USB/UART adapter is based on an FTDI chip : good, I like these ones because they present a serial number.
When working under Linux, you can set some udev rules to create an alias, for example /dev/mySpecificSerialDevice --> /dev/ttyUSBx. Whatever the order of detection, the USB port it's pluged in, etc, you'll be able to identify your device based on this FDTI serial number and always use the same /dev/mySpecificSerialDevice. With the CB2, you should be able to use Cutecom for example.
When working under Windows, well, it's plug and pray ... It may work as intended for weeks or months, and, one day, for no reason at all, Windows will decide that the adapter you never unplugged will change from COM3 to COM12 ... Windows is magic !
Be careful though, there has been some knock of, and few years ago, FTDI released drivers that killed the fake chips ! Pffff, smoke ... But I never witnessed such retaliation myself ...
That being said, I'm surprised it didn't worked at 38400 bps. I've been using few FTDI to debug STM32 FWs at 460800 without any problem ! Did you changed the settings in Teraterm ? (perhaps I missed it in the video)
Wow, that's a throwback and a half. Hyper Terminal! Software that somehow escaped from windows98. :-D It brings back so many memories, and they are all bad. It belongs in the Recycle Bin.
its a nice little computer very limited but a good teaching tool ......nice vid Noel
Great video. Thanks Noel!
My pleasure!
No need to open the serial converted, you can use the continuity test of your multi meter to check the wiring. For a 1-to-1 connection you would need to cross all lines, so rotating the connector 180 degrees from one side to the other helps. The serial connector choice on the CB2 seems wrong, it should be a female connector on the board, replacing the connector would be useful. Usually serial communication with micro controllers works at TTL levels. Putty is an excellent terminal program with lots of features
When I saw Ch340 in the device manager I knew it will be desasterous... Take a board with CP2102 and jumpers for TTL and CMOS levels etc.
Atmel/Microchip make an ATMEGA 1284P which is a dip-40 and has 16k of static ram and 128k of flash, so in principle a CB2 could be made with 4 times the memory, and plenty or room for an upgraded editor and interpreter.. I don't know off the top of my head if it is pin compatible, although I imagine it is.
There is certainly scope for this device, I always think its incredible what can be done with microcontrollers, and considering the ATMEGA is not the newest device I love the simplicity and cheapness. I think it would probably not be too hard to put in an emulation of a sound chip like the AY-3-8910 or SN76489. I have programmed ATMEGAs to generate polyphonic multi waveform sound in the past, although it does use a lot of processing power so something simpler would be better. Then with some support in the basic for it, it would make a fun platform to allow people to make their own "chiptunes".
You also get to enjoy the experience of messing with RS-232 which is very retro computing!
thank you for posting. as i remember, i think one of the comments on your cb2 earlier video suggested a usb-ftdi adapter [similar to the little red pcb gizmo you used] instead of the usb2rs232 dongle you started w/. also, while waiting for the fem2fem db9 gender changer, would a few fem2fem dupont jumpers have worked ? perhaps the rs232 pins are too large in dia for the dupont jumpers. please take care & stay safe.
Maybe it's not in the spirit of retro computing, but there are some amazingly powerful microcontrollers around a similar price point to the ATmega644 these days - picking a random one, the STM32F730 has a 32-bit ARM Cortex M7 capable of 200MHz, 276KB of SRAM, an FPU and a boatload of peripherals for just 11 USD in single quantity!
Amazing how cheap computing power is these days, but there's still something satisfying about getting every last bit of performance out of an 8-bit CPU
Definitely! I'm planning on building some similar microcomputers based on much more powerful hardware. Should be an interesting comparison.
Well, this dragged me back to the second semester of my Comp Sci degree in 1984
Delay is, probably, configured in hyperterminal, because of no flow control, to prevent remote system from skiping symbols on overflow.
And you, usually, don't need +5V from remote system for powering USB-to-UART adapter. It usualy takes enough power from USB, so only RX, TX and GND needed.
19:05 Did you change the baud rate at both ends? I mean on the CB2 and on the PC?
The AVR-MCU make use of the Harvard architecture and separates program (AVR: flash) from data memory (AVR: RAM, EEPROM). The 80s home computers are make with von Neumann architecture, where program and data shares the same memory. This means for CB2 it's not possible to place executable machine code into ram and execute it. That's a big differrnt to Z80, 6502 etc.
How many ways the IT industry managed to screw up something as simple a serial port... And yeah, lot of the cheap "usb to serial" adapters are junk.:( Great detective job as usual!
Yeah, seriously. The quality of some of those adaptors is abysmal. And then you don't know exactly where the problem is: the driver, the hardware, the way the computer handles things...
The screw up is that that particular adapter doesn't send data at remotely the correct speed when configured at 1200 or 2400 bps. Other than that, it would be probably work fine, even with the 0-5V range.
Great video, Assembly perhaps to get around the limitation of 100 lines? Maybe that is an apples/oranges mistake on my part.
Yeah, I didn't get into assembly but that supposedly would get totally around that and just be limited by the (small) amount of internal memory.
You are not actually limited to 95 lines of total code like the video mentions. You can use the CALL function to combine programs (total 8 programs) for a total of 760 lines of BASIC code. And if you write your programs with functions, you can recall them at any time ;)
@@cb2micro Why is there this 100 lines limitation ?
@@freeeflyer It's a matter of available memory. BUT please read the comments. You can use the CALL function to combine more than one program positions. This will lead you to a total of 760 lines of basic code, if you use all 8 program positions. So there is no actual 100 line limitation, but 760 lines limitation :) This does not count the functions that can be re-used many times within your code :)
@@cb2micro
I read the comm. I just wanted to know the reason.
RS232's specs are +15v to -15v differential. While +3v and -3v are the absolute minimum ratings (in the spec), the 5v differential is getting awfully close to that minimum. With this low voltage, the cable length will have to be small, and may be susceptible to errors. A MAX232 chip would have been better (with a proper voltage differential), but I doubt they are made now days.
I do not know if you seen it, but there is a simple Vic20 emulator for the Arduino Uno. It does not support graphics or sound but it does emulate the CBM BASIC 2.0 environment well through a terminal.
I forget where I seen it but you should be able to find it quickly under google.
I hadn't seen it but that sounds like a cool project. I'm kind of surprised it doesn't do graphics emulation though. I guess the Arduino can't handle it.
@@NoelsRetroLab - I found one that does its own video but no true graphics more. I'm sure there are better ones than this one. Should be simple for you. Due to the small footprint the Arduino Uno/Mini/Nano, the Emulated Vic20 has about 1.25K RAM.
create.arduino.cc/projecthub/janost/the-nano-vic-20-e37b39
Looking at the schematic for this thing, I gotta say, I wasn't expecting the way they got the -V for the serial port...
I don’t quite understand the bps calculations around minute 10. Did you confuse micro and milliseconds, or did I misunderstand something?
21:45 There are no bigger AVR's without going to SMD parts, this is as big as it gets.
When your hobby turns into work. :-D
USB to serial cables never quite work well, and sometimes they are 100% rubbish. There's usually issues with timing, voltage levels, or both. You have both issues. Any surprise why my main workstation has four COM ports?
I take it you had to install internal serial port cards? I don't believe most motherboard come with serial port these days, right?
@@NoelsRetroLab There will be one or two com port headers on the motherboard. even today. PCI serial cards are another option, new or second hand.
I have that same green cable for about 20 years and it is a headache, the cable uses a chip intended for HID (cheaper) and not a UART chip, windows detects it wrong, it thinks it is a human interface device and the driver in many cases is poorly programmed. I still use it (but at my own risk) with a linux laptop, I open the corresponding / dev and I have no problems, I use it to connect devices such as smart card readers, industrial equipment, etc.
The truth is that for usb to RS232 the best thing is a cable that contains the FT232 chip as said above unless you have a lot of experience in the field.
And beware the FT232 is a very counterfeit chip.
it would be nice to see if you can work on the CB2 and maybe upgrade its capabilities that would be fun to see.
Hi Noel, I've got my CB2 Microcomputer up and running. BUT, I can't get hyperterminal to even start. It keeps asking for area codes. I don't know what it means. Can you please help?
Urgh. Yes, that's "normal" as far as I can tell. Seriously! I type anything and then move on. But seriously, drop that and go get TeraTerm instead. Much better and it doesn't have that weird delay.
@@NoelsRetroLab O.K. Thank you.
12:18
I’m seeing you suffering to debug the PC output and I’m like
JUST GET A INDUSTRIAL COMPUTER WITH SERIAL PORTS
Just in case you decide to try an industrial motherboard for the serial, I recommend you the Asrock IBM150
It has 3 external COM ports 2 internal COM ports, and you can adjust the mode and voltage if I’m not wrong
Using different program slots is the same as the Casio PB-110.
I've got to get one of these. I think I have sent him an email. (I just don't understand how they work. LOL).
nice computer good enough for driving a video and audio chip. Yamaha OPL3 or OPL4 Yamaha V9990 video chip.
Why not just go for a real RS232-to-USB cable as the kit intends?
Ok, your thought as well later in the video :)
38k4 is not 38k, the standard is baud rate is 38400. That’s probably the reason.
Hahaha USB went into the laptop wrong way around first time. Of course it did. Aaaaaarghhh.
Hahaha... I didn't even notice until now! :-)
Windows needs a DRIVER for the cable? just plug it in on linux and its works out the box
Linux needs/uses "drivers" (kernel modules quite often) too, it just happens to include a trillion generic ones.
This "cable" isn't a straight-through cable. It's a USB UART conversion chip (CH340), inside a cable. Yes, Linux does include the CH340 driver, as well as the common FTDI one, and probably others.
That USB-serial adapter is so bad, I would have tried to get my money back. I don't use serial very much, but when I do, I like to use the ports on the motherboard of my desktop or the base station of an old laptop.
Oh, regarding your desire for more memory during program execution time, please see this extension that you can easily build cb2.qrp.gr/extensions/#4._External_EEPROM_expansion
CH340 is pure chinesium xD
Your wonderment about the "gender changer" surprised me.
🇨🇦
heh, the asus laptop keyboard and surround is a blatant rip off of the early 2012 style macbook pros. I'm surprised they didn't get sued for that 😂