Michael wrote:
I was hoping there was an existing electronic copy somewhere. I cannot ask you to scan a 200+ page book but it was very kind of you to offer.
Book 3 covers the expansion board that adds a 6522, more memory (2716 and 2114), the cassette interface and rs232. It also covers a separate memory expansion card.
Depending on your exp/ability these cards would be better redesigned, unless your goal is to replicate the Junior exactly. If it was me, I would make a small ram card with a 32k ram and 32k eeprom and block out the I/O addresses. Then I would make an I/O board with a 6522 and a 6850, so that I could add a serial port, SPI for an SD card and I2C.
What I'm trying to say is that a lot of the book is not really relevant today unless you have the pcbs. The bits that are of use/interest I could scan for you.
It's book 4 that is really useful as it digs into the firmware upgrades that make Junior a more useable machine. I could scan the assembler listings, but really I think you would want/need the whole book.
Michael wrote:
May I ask if you have an actual Junior Computer to go along with that book set?
Cheerful regards, Mike
Sadly, no... I bought the books, about 15yrs ago, I was going to build one but couldn't get hold of the pcbs and then life got in the way. Now I have time and have recently started to put together a system from scratch, but you asking about Junior has started me thinking.....