A Lockdown Brightened By A Library Of Vintage Usborne Books

Lockdown is boring. No, let’s emphasize that, lockdown is really boring. Walking for exercise is much less fun than it was last year because it’s a wet and muddy February, and with nowhere open, a rare trip out to a McDonalds drive-through becomes a major outing. Stuck inside for the duration we turn our eyes to some of the older ways to wile away the time. Books. Remember them? In doing that I found that the friend whose house I’m living in has the whole library of Usborne children’s computer and technology books from the 1980s. Suddenly a rainy day doesn’t matter, because we’re in a cheerful world of cartoon robots and computer parts!

When Kids Learned Machine Code

A comprehensive selection to get one's teeth into.
A comprehensive selection to get one’s teeth into.

If this leaves you none the wiser, it’s worth explaining that during the 1980s home computer boom there was no Internet handily placed for finding out how your new toy worked. Instead you had to read books and hoard the scraps of information they contained. Publishers responded to this new world of technology with enthusiasm, and the British children’s publisher Usborne did so in their characteristic entertaining and informative style. For probably the only time in history, children were presented with mainstream books telling them how to write machine code and interface directly to microprocessors, and those among them who probably now read Hackaday took to them with glee. They remain something of a cult object among retrocomputing enthusiasts, and fortunately a selection of them are available for download. Usborne are still very much in business producing up-to-date books educating today’s children, and to promote some of their more recent titles for the Raspberry Pi they’ve released them in electronic form. Continue reading “A Lockdown Brightened By A Library Of Vintage Usborne Books”

Programming The 6502 One Nibble At A Time

[Quinn Dunki] keeps rolling with her 6502 based computer build. This time around she’s added some memory to store the programs, but needed a way to get that code into the device. Above is her solution, a bank of hex switches used to program the 8-bit command and 16-bit address for each line of machine code.

This is a continuation of her Veronica project. The last time we saw it she had hardwired the logic levels for the data bus, but that’s no fun since nothing can actually be computed. [Quinn] picked up an SRAM chip which will store the program. It’s compatible with the 6502’s memory bus, but needs a bit of extra circuitry for her to be able to hand program it with this switch bank. She used some tri-state buffers to switch between connections to the processor, and to the hex switches. This way, she disconnects the RAM from the processor using the buffers, uses the switches and push button to clock in the program, then patches the RAM back into the computer.

Seeing this process in the video after the break certainly gives you an appreciation for what an improvement the punch-card system was over this technique. Still, seeing this is a delight that we’d like to try! Continue reading “Programming The 6502 One Nibble At A Time”