Question for backfill — ZXNet «real.speccy»

From Sergey Karachentsev To All 1 October 1999

Hello All!

In what order are the Z-80 INIR and OTIR commands executed?

INIR OTIR

1. reading a byte from port (BC), issuing a byte from (HL)
and writing to (HL) via port (BC)

2. increment HL and decrement B

3. if B=0 then go to action 1.

???? IS THIS SO????

With respect, Sergey Karachentsev.

From Evgeny Milun To All 2 October 1999

Hello Sergey !

Friday October 01 1999 12:11, Sergey Karachentsev ─── All:

SK> 1. reading a byte from the port (BC) issuing a byte from (HL)
SK> and writing to (HL) via port (BC)
SK> 2. HL increment and decrement B
SK> 3. if B=0 then go to action 1.
SK> ???? IS THIS SO????
IMHO, all my experience shows that this is exactly the case.
Have you encountered anything contrary to this?

Good luck! Evgeny. (Aka 2:5057/18.73)

■ The night is shorter than the day... The day will kill me... The world of illusions burns down in it. (C) Aria.

From Dmitry Lomov To All 2 October 1999

Hello, Sergey!

Once, Fri Oct 01 1999 13:11, Sergey Karachentsev wrote to All about [Question for backfill]:

SK> In what order are the Z-80 INIR and OTIR commands executed?

INIR: cbr(4) ocr(4) prd(4) mwr(3) iop(5) [iop(5)]
OTIR: cbr(4) ocr(4) mrd(3) pwr(4) iop(5) [iop(5)]

only one doubt - somewhere someone shouted that these commands pre-increment
port addresses.

All the best.
Dmitry.

... LD..X-TRADE... [ZX]

From Sergey Karachentsev To All 4 October 1999

DL> INIR: cbr(4) ocr(4) prd(4) mwr(3) iop(5) [iop(5)]
DL> OTIR: cbr(4) ocr(4) mrd(3) pwr(4) iop(5) [iop(5)]

How to understand this encryption?
It will take me a long time to get a book with these abbreviations will pass.

With respect, Sergey Karachentsev.

From Sergey Karachentsev To All 4 October 1999

Hello Ivan !

IM> command INI command OUTI
IM> loop:
IM> IM buf,(BC) LD buf,(HL) ; here is the initial B
IM> ----------- DEC B -----------
IM> LD (HL),buf OUT (BC),buf ; and here it is already reduced
IM> ---------- INC HL -----------
IM> JR NZ,loop ; checking register B for Z !!!

IM> buf is an internal temporary buffer in the processor.

In this case, working with the HDD buffer should look like:

read write

... ...
LD HL,addr LD HL,addr
LD BC,#00AF LD BC,#FFAF
INIR OTIR
INIR OUTI
... OTIR
OUTI
...

for port #AF

Regards, Sergey Karachentsev.

From Dmitry Lomov To All 5 October 1999

Hello, Sergey!

One day, Mon Oct 04 1999 09:47, Sergey Karachentsev wrote to Dmitry Lomov about
[Question for filling]:

SK> * Forwarded from area 'REAL.SPECCY'

SK> Hello Dmitry!

From Ivan Mak To All 5 October 1999

Greetings, Sergey!

On the day Sergey Karachentsev wrote to Ivan Mak:

[skip]
SK> In this case, working with the HDD buffer should look like:

SK> read write

SK> ... ...
SK> LD HL,addr LD HL,addr
SK> LD BC,#00AF LD BC,#FFAF
SK> INIR OTIR
SK> INIR OUTI
SK> ... OTIR
SK> OUTI
SK> ...

SK> for port #AF

That's right. And there should be no problems with this. Also, reading/writing to increase
speed is best done using multiple INI and OUTI commands. Those. make cycles
expanded. Or partially expanded.

Wow! The Protoss are attacking my Zerlings! It's time to get going. Ivan...data-saferedirecturl="https://www.google.com/url?hl=ru&q=http://www.atlant.ru/peters&source=gmail&ust=1785433329286000&usg=AOvVaw2Ehe_mAtrzm50Fm_CLtBJp">www.atlant.ru/peters *

From Oleg Grigoriev To All 6 October 1999

DL> there is only one doubt - somewhere someone shouted that these commands with
DL> pre-incremented the port address.

That is the conclusion. outd and outi. I don’t remember about otir.

[ WBR, Oleg. ]
[ 18:49 6 October XXXIV A.S. ]