Category: Sharp

An SC61860 bug since 25 years

Incredible — a bug in the SC61860 CPU used in classic Sharp devices has been fixed after 25 years!

Usually, a CPU bug is spotted quickly because everything crashes. But this one was a subtle side effect in batch instruction processing.

When I requested a batch of 0xFF, the loop exited without doing anything, instead of executing 256 times.

Turns out, it was just a while () {} that needed to be replaced with a do {} while ().

Now, the LC-3 compiler works correctly — it’s the one that uses 0xFF batches, unlike the standard ROM which never does.

It took me ages to find this bug, I was so convinced my algorithm was solid. obviously, after 25 years of faithful service…

PockEmul 2.9.0 New Release

Dear PockEmul’s fans, we are pleased to announce the new PockEmul release. It will be available in the next few days.

This new version brings several new models and some new features:

  • New Casio VX-3, VX-4 and FX-870p package
  • New Casio Almost PB-100, Almost PB-300, FP-12 and FP-40 (SB-42) package.
  • New CE-15x extension for PC-1500 series.
  • New Sharp PC-E500Jap and PC-E500-BL.
  • New HP-10c.
  • New Search feature for Local and PockEmul Cloud storage.
  • Share a Cloud session by QRCode.
  • CE-1600p new pen head rendering.
  • Keyboard Simulator new layout and overclocking up to x100.
  • A new ‘Lock Position’ feature in the contextual menu that fixes the position of a device on the screen.
  • The XP-140 Monitor Card is available for the X-07.
  • A lot of bug fixes.
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