- PC-8200 Technical Notes
Hardware port mappings, Description of ROM routines, Math routines,
Information for Option-ROM, Machine-code file handling routines,
BASIC program file handling routines, Internal structure of the
PC-8201A RAM file system, and tape format.
- NEC PC-8201A Service Manual w/Schematics
The NEC PC-8201A Service manual is a complete reference for servicing
the hardware of the machine, and includes: Functional Specifications
(Logical, Physical, I/O, Software interface, Human interface,
Performance, Accessories), Disassembly/Reassembly instructions (Cover, LCD,
Keyboard, Power Supply board, Main board), RAM/ROM insertion, Battery
installation, Operation tests (Power supply, CPU, CPU Clock, Calendar
clock, LCD, SIO1/SIO2/RS-232C ports, BCR port, Parallel port,
CMT interface, Speaker, Keyboard), Troubleshooting abnormal operation,
IC removal, Parts lists, Circuit diagrams, Schematics.
- NEC PC-8201A Technical Reference
Memory map, how to use 2nd ROM, how to use 2nd/3rd RAM banks,
Understanding the RAM file concept, Directory structure &
configuration, RAM organization (bookkeeping area, VRAM area
for LCD, BIOS bookkeeping, FCB), RAM File handling, Hardware
specs for: LCD Interface, Keyboard interface, CMT interface,
Serial interface, Barcode interface, Parallel interface, and
finally the System bus and memory control circuitry. It is a
*must have* if you're a serious programmer for the NEC.
- NEC PC-8300 Technical Reference
Here's the same document for the 8300, with a few additions.
The 8300 can use a 128K ROM and bank switch between four 32K
images contained inside. The additional circuitry to do
this is not present in the 8201A. Also, the 8300 had support
for an optional internal modem.
- Designing Cross-Compatible programs for the Model 100 & NECs
It is actually fairly simple to design your program from the ground up so
it can run unmodified between the Tandy and NEC models
of notebooks. You reach the widest audience this way,
plus it adds an interesting challenge to your development
project. In the Windows world, you, the consumer, certainly
wouldn't tolerate a situation where a Windows program was
specific to an IBM computer and required changes to run
on your Dell! :-) Think about embracing the idea of
cross-compatible software development for the "Model T"
- Converting Model 100 programs to work on NECs
Here are the main issues of concern when trying to convert
a program written for the Model 100for use on the NECs.
With all of the software out there available for the
Model 100, this information can be quite beneficial.
- SIO1 / SIO2 / RS-232C port information
Here you'll find pinouts and I/O port control information that let you use those extra ports
on the back of your NEC.
- NEC PC-8300 can emulate the 8201A!
How do you switch between the "8201" emulation mode on the NEC PC-8300? Find the info here!
- Converting the NEC battery pack for NiCad's
By soldering in a jumper and a resister into the battery
pack, you've just converted it into a NiCad cartridge
which will charge four NiCad's off of the 8.5V power supply.
You're free from buying those pesky alkaline AA's forever.
- Creating your own 32K memory module!
Here are plans for creating your own 8K and 32K memory
modules from some very inexpensive chips. If you're good
with a soldering iron, this might be the ticket for expanding
your PC-8201's banks of memory. (Not applicable to the NEC
PC-8300 - It already comes with a full 64K which is the maximum
- Tandy Portable Disk Drive Cable Revealed
You have a Tandy Portable Disk Drive (TPDD or TPDD2), but no
cable...or a cable that is broken. What do you do? Thanks to
Marty Goodman, you can build your own cable with a little ambition.
- NEC Y2K Fix
If you have access to an EPROM programmer, you'll be able to
implement a cosmetic Y2K "fix" for your NEC PC-8201 or 8300.
There's just a couple of ROM locations that need to be patched,
and you'll never have to see a "19xx" date on the system menu
- Model 100 Y2K Fix
The same cosmetic fix is possible on the Model 100 as well,
however you'll also need to be handy with a soldering
iron. I followed these same instructions and it took me
about three hours from start to finish. Thanks to William
McCrosky who originally reported this successful hardware
solution. (PDF format, 200k)
- Getting downloaded files into your NEC
. . . The HOT Setup: The most flexible option for loading & saving files between
your NEC and your DOS or Windows Desktop PC would be the NADSBox & TS-DOS combination. The NADSBox
device is available for purchase from Club 100. In the
absense of a NADSBox, another option would be to use the DESKLINK & TS-DOS combination. Plus, there
always is the old fashioned terminal program to terminal program connection that you can set up for
manual uploads & downloads between computers. Information about both all of these methods is just a
- How I used 22DISK to read my CP/M PICDisks
The PICDisk was one of the specialized disk-drive systems
available for Model T computers. Not just a disk drive,
it literally turned your Model 100 or NEC into a full blown
CP/M computer. Unfortunately, mine was stolen way back in
1990, and I had a ton of disks that I could no longer read.
Here's how I "resurrected a dinosaur" and regained access to
those CP/M disks, using software called 22DISK. If you have
old CP/M disks and you want to read them from a Windows
machine, 22DISK is your tool!
- Archive of NEC PC-8401/8500 "Starlet" Discussions from GEnie
This is the first of (hopefully) many bits of technical
information that I will post on this web site. You might
find answers to questions about the Starlet machines
within this document.