Questions tagged [hx-20]

for questions about the Epson HX-20 laptop computer

Filter by
Sorted by
Tagged with
10 votes
1 answer
288 views

What to replace the belt in the cassette drive of an Epson HX-20 with?

I am the owner of an Epson HX-20 laptop computer. It runs well except for the builtin cassette drive which doesn't seem to work reliably. After carefully disassembling it I found that the belt seems ...
fuz's user avatar
  • 1,572
8 votes
1 answer
486 views

Why does my Epson HX-20 apparently have much less RAM than expected?

When I enter: STAT ALL On my Epson HX-20, I get the following output: P1: 419 Bytes P2: 86 Bytes P3: 0 Bytes P4: 0 Bytes P5: 0 Bytes RAM FILE 256 Bytes MEMSET 2624 105 Bytes Free As I ...
harlandski's user avatar
  • 2,885
6 votes
3 answers
1k views

How to connect an HX-20 to a monitor via the RS232 port?

Using & Programming the Epson HX-20 Portable Computer by Eric Balkan has a tantalising passage on p. 172*: T.L. Ronson of the HX-20 User's Group also notes that a monochrome monitor can be ...
harlandski's user avatar
  • 2,885
2 votes
1 answer
894 views

Why did this Hitachi 6301 assembler routine only work once?

I am trying to learn assembler on the various retro machines I own, or am about to buy. Today I tried converting this 8080 routine (which worked, repeatedly): | START: | MVI A,0 | 8000 | 3e | | ...
harlandski's user avatar
  • 2,885
2 votes
2 answers
289 views

(How) can I safely use direct addressing for machine code routines on the Epson HX-20?

I am working through the exercises of Lance Leventhal's 6800 Assembly Language Programming on my Epson HX-20. My understanding is that the HX-20's Hitachi 6301 processor is compatible with the ...
harlandski's user avatar
  • 2,885