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Back in the 1980's amongst other things I made commercial laser printers that emulated line, dot matrix, daisy wheel printers and other laser printers. Initially memory was very expensive and limited thus lines were compiled and sent to the laser printing engine on the fly. When memory became...

10Base2 is designed for 50 ohm characteristic impedance. It's rather tolerant but you may encounter signal problems such as unwanted signal artefacts if using 75 ohm characteristic impedance. Only ground one of the terminators NOT BOTH! The best way to test your installation is with a TDR (Time...

If you're testing with %FF's it's best to weakly pull up the data lines via resistors to VHigh to prevent the bits from changing. Likewise for NOP %00 testing but pull down to ground. The last thing one wants to do is tie the data lines directly to GND or VCC.

A funny soldering job on the adapter card. The SMD components seem to have far too much solder on them. One can replace the square pins with appropriate round pins from companies like mill-max.

Replace DJNZ with DCR B JNZ LOOPB

Not bad. Partial signs of life!

The Aussie Hi-Tech C!

Here's an interesting blurbette from ASIX "In order to be compatible with some legacy software, some users might need to remap the assigned I/O addresses of AX99100 Parallel/Serial ports to Legacy (ISA type) I/O address (such as 378h, 3F8h, etc.). It is possible on DOS and Windows 95/98/ME...

Great to know! Now for a PCI-E based one.

The NSC800 has got quite a few other enhancements that make it incompatible with some undocumented instructions and existing Z80 features. e.g. 8 bit autoincrementing refresh (R) register, multiplexed data/lower address bus.

Do it the old fashioned way: make a cast plug from the broken piece, infill the missing bits and make a new one out a material that can handle the torque.

Someone suggests that you contact Analog Devices because they now own Linear Technology.

Note the@9's only appear if the CPU is executing repeated RST 38Hs (op code FFH).

The ladder has mazes comprising of 79 columns and 20 rows. How is this going to work on a TRS80 with 64 columns and 16 rows?

The AM radio and other spurious emissions from home computers caused TVI and other safety issues which forced the appropriate FCC and worldwide equivalent regulations to be formulated. Welcome to the world of EMC (electromagnetic compliance)!