IDE interface with RTC 4

IDE interface with RTC

Dec

4

2011

There are two things in my design still missing to declare completion of basic hardware – real-time clock and IDE interface. Hence, my recent project activities concentrated on these two elements. RTC and IDE will occupy a dedicated expansion board and will be built in a way to keep hardware complexity to the minimum. RTC ...
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Design - I/O

New memory and UART boards

New memory and UART boards

Nov

1

2011

It is difficult to lay out boards properly. This task requires a lot of patience and experience, otherwise you end up with poorly routed boards, hundreds of vias or lengthy signal traces. Somehow I am still unable to avoid all these imperfections and my boards are not quite how I would like them to be. ...
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Construction

Memory system update

Memory system update

Oct

29

2011

My memory system has recently undergone an update to hardware design. Originally I planned and implemented four memory bank registers – two for lower and upper 32kB of code, and two for lower and upper 32kB of data (see this post for details). With hardware able to address maximum of 128 banks via 22-bit address ...
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Design · Design - memory

EPROM emulator hacked and working

EPROM emulator hacked and working

Oct

2

2011

The EPROM emulator I mentioned in my last post now works with the memory board. Making it work was an easy task and required a few simple hacks in hardware and software. Now I have a convenient and reliable development environment based on real hardware, and free of the hassle of EEPROM programming. I know ...
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General

Monitor/OS taking shape, EPROM emulator 5

Monitor/OS taking shape, EPROM emulator

Sep

14

2011

I have just returned from a two and a half week training combined with short vacation. I haven’t posted for a while but the project is well alive and it will regain momentum now when I am back home. Immediate plans are to complete the Monitor/OS with a little help of a nice gadget described ...
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Software

Assembler and instruction set update 2

Jul

31

2011

I am slowly progressing on my simplistic OS/Monitor development. It is only a little fun, mainly because I do not have a functional simulator (i.e. emulator) of the computer and I have to test every bit of assembly code on real hardware. For that I have to constantly switch from Linux (where my development toolchain ...
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Design - ISA · Software