From 561bac75579391c14e47eaccfabdf9eda98855da Mon Sep 17 00:00:00 2001 From: Thomas Albers Date: Wed, 27 Jul 2022 18:13:20 +0200 Subject: Initial commit --- src/z80/prototype2.org | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 src/z80/prototype2.org (limited to 'src/z80/prototype2.org') diff --git a/src/z80/prototype2.org b/src/z80/prototype2.org new file mode 100644 index 0000000..ba19bd7 --- /dev/null +++ b/src/z80/prototype2.org @@ -0,0 +1,51 @@ +#+TITLE: Prototype 2 +#+DATE: <2021-03-03> +#+SETUPFILE: ../../options.org + +#+BEGIN_COMMENT +m4_define(`_REL_HEADER', `Next: Prototype 1 Up: Z80')m4_dnl +#+END_COMMENT + +{{{date_place(Bremen, Germany)}}} + +#+CAPTION: Prototype 2 +[[https://thomaslabs.org/media/prototype2_1.jpg]] + +Because when moving to Bremen, I wasn't able to take my old Prototype +with me, I had to build a new one. This time though, I needed +something easily modifiable. + + +One of the disadvantages of my first Prototype, was the fact, that it +took me around 3 days to build and, because it was soldered, it was +difficult to modify. This made experimenting with new ideas somewhat +impractical. + +Prototype 2 would be a prototyping tool, as such, it had to be built +with a technique, that allowed for the electrical stability of a +soldered circuit, but with the flexibility of a breadboard. + +This time I chose the wire wrap assembly technique, as it met all +requirements. + +The following is a list of what I was able to accomplish thanks to +Prototype 2 + +- New memory banking system that would allow it to handle up to 4 MiB + of memory, instead of the default maximum of 64KiB. + +- Add a RTC + +- Add video capabilities using a 480x320 18-bit color display + +- Dual serial ports with complete modem control lines + +#+CAPTION: Prototype 2 together with screen +[[https://thomaslabs.org/media/prototype2_2.jpg]] + +It didn't take long until Prototype 2 became incapable of fulfilling +its task. Once it was clear, which parts would definitely be part of +the final design, the flexibility of wire wrapping was no longer +needed. Added to this, the circuit experimented detrimental voltage +drops, due to the length of wire used. It was now time to design a +third prototype, this time using a PCB. -- cgit v1.2.3