Hayes on Speccy — ZXNet «real.speccy»

From Sergey Kachalov To All 5 October 2002

Does anyone have a wiring diagram for the subject. I want to connect the Ext modem to the Specky

From Kirill Frolov To All 6 October 2002

Press RESET immediately, Sergey!

05 Oct 02 11:29, Sergey Kachalov wrote to All:

SK> Does anyone have a wiring diagram for the subject. I want to connect the Ext modem to

Kondratieff circuit <--> pisish multicard <--> modem.

The internal modem is connected directly to the computer bus through a
special adapter that converts the address on the Spectrum address bus to the modem address on the ISA connector and buffers the signals.
There are several popular options for such adapters:
Kondratievskaya (the most popular), Shepelevskaya, SMUC controller
for the zs-scorpion computer. All adapters convert
the address on the microprocessor bus to the address on the ISA connector in different ways, so
to program a modem connected via different adapters
you have to use different port addresses. As a result,
some programs work only with modems connected via
one adapter, some programs work with all adapters, and
some programs come with an external modem driver.

The Kondratieff modem connection scheme is the most
popular and can be implemented without problems on almost any Spectrum-compatible computer, however, in its original
form it is not without some drawbacks. The main advantage
of the scheme is the ability to receive interrupts for
the processor from the modem and a relatively conflict-freeaddressing
ports. The Shepelevskaya circuit in the original did not have the ability
to transmit interrupts from the modem to the processor and had port addresses that conflicted with other hardware on many computers;
there are modifications of the Shepelevskaya circuitry that are devoid of these
disadvantages. The SMUC controller developed by the St. Petersburg company
Scorpion for its computer has port addresses available
only when the ROM of the TR-DOS system is connected, which incredibly
complicates programming of the modem, in addition, due to errors in the
controller, the use of interrupts is almost impossible.

Original Kondratieff adapter circuit for connecting
an internal modem:

DD1
__ +---+
RD -----------------+1 | _____
| +------- IORD# (modem)
+---+ |
DD1 | +---+
+---+ |
A4 ----+1 | |
____ | +----+
IORQ --+ | |
+---+ | DD1
| +---+
+---+1 | _____
__ | +---+-- IOWR# (modem)
WR -----------------+ | |
+---+ |
|
+-----+
|
| DD2
| +--------+
+5v - | ---o R |
| |Q +-----+
+----/ C | |
| | |
A11 --------> D _ | |
_____ | Q O-- |
RESET --+---o S | |
| +--------+ |
| |
| DD3 |
| +---+ |
| |1 | |
+----+ O--------------- RESET (modem)
| | |
+---+ |
|
|
|
| DD1
DD3 | +---+
+---+ +--+1 | ---
|1 | | +------ NMI
(modem) IRQ4 ----+ O---------+ |
| | +---+
+---+

A8 ------------------- A0 (modem)

A9 ------------------- A1 (modem)

A10 ------------------- A2 (modem)

D0..D7 ---------------- D0..D7 (modem)

+5v -------------------- A3..A10 (modem)

GND -------------------- AEN (modem)

Список элементов:

DD1 1533ЛЛ1
DD2 1533ТМ2
DD3 1533Л1

Сигналы отмеченные в скобках "(modem)" подключаются к
соответствующим контактам ISA слота для модема, остальные
сигналы подключаютсяdirectly to the computer bus.

Access to modem registers through ports

Modem registers are accessible through microprocessor I/O ports.

The address is calculated as follows:

0xF0EF + (0x0800 if NMI interrupts are disabled) + (register_address*0x100)

The modem interrupt enable trigger is switched only when
output to the ports modem.

Modified Shepelev circuit, supported in the Melon program:

D0..D7 ----------------------- D0..D7 (modem)

A8 -------------------------- A0 (modem)
A9 -------------------------- A1 (modem)
A10 -------------------------- A2 (modem)
A11 -------------------------- A3 (modem)

A12 -------------------------- A8 (modem)
A13 -------------------------- A9 (modem)

+5v ---------------------- A4 (modem)
+5v ---------------------- A5 (modem)

GND ----------------------- AEN (modem)

+---+
A14 --------+ 1 |
| +---+
A15 --------+ | |
+---+ |
DD1.1 | +---+
+--+ 1 |
| o----+---- A7 (modem)
A6 ---------------------+ | |
+---+ +---- A6 (modem)
DD2.1

____ +---+
IORQ ----+---+ 1 |
__| | +----------- IORD# (modem)
RD -----(---+ |
| +---+
| DD1.2
| +---+
+---+ 1 |
__ | +----------- IOWR# (modem)
WR ---------+ |
+---+
DD1.3

+---+
GND -----+ 1 |
_____ | o----------- RESET (modem)
RESET -+ |
+---+
DD2.2

List of elements:

DD1 1533ЛЛ1
DD2 1533ЛЛ1

Access to modem registers via ports

Modem registers are available through the input-output ports of the microprocessor,
the port address is calculated as follows:

0x38BF + modem_register_address

The above circuits have some drawbacks. For example, they
most likely will not work if you connect the modem and
computer with long (>10 cm) wires. The problem here is the excessive inductance of the conductors. does not work, you can
try to pass the signals A8,A9,A10,IOWR and IORD through a Schmidt trigger installed in the immediate vicinity of the ISA slot.

SMUC adapter for connecting a modem:

The SMUC controller from Scorpio has a slot on the ISA board for installing a
modem. Since the basis of the SMUC controller is a programmable logic chip from the company. "Altera" with unknownthe contents of the diagram will not be shown.

The modem registers are accessible through the microprocessor I/O ports.
It is also possible to use interrupts, but there are some problems there.
There is no complete information about the controller. We only know how to calculate the addresses
registers of the modem:

Port address = 0x78FE + (register_address * 0x100)

The port address is in the TR-DOS port space!
Input and output can be done as follows:

Input: ; BC=port address --> returns the value in reg. A
push hl
ld hl, 0x3ff3
ex (sp), hl
jp 0x3d2f

Output: ; BC=address, reg. A=value for output
push hl
ld hl, 0x3ff0
ex (sp), hl
jp 0x3d2f

short (8-bit) ISA slot pin assignment:

+---------+---------------+-----------------+---------+
| contact | signal | signal | contact |
+-+-----+-+---------------+-----------------+-+-----+-+
| A1 | IOCHK | GND | B1 |
+-----+-----------------+-------------------+-----+
| A2 | D7 | RESET | B2 |
+-----+-----------------+-----+-----+
| A3 | D6 | +5v | B3 |
+-----+-----------------+-------------------+-----+
| A4 | D5 | IRQ2/9 (*) | B4 |
+-----+-----------------+-------------------+-----+
| A5 | D4 | -5v | B5 |
+-----+-----------------+-------------------+-----+
| A6 | D3 | DRQ2 | B6 |
+-----+-----------------+-------------------+-----+
| A7 | D2 | -12v | B7 |
+-----+-----------------+-------------------+-----+
| A8 | D1 | OWS2# | B8 |
+-----+-----------------+-------------------+-----+
| A9 | D0 | +12v | B9 |
+-----+-----------------+-------------------+-----+
| A10 | IOCHDRY | GND | B10 |
+-----+-----------------+-------------------+-----+
| A11 | AEN | SmemWR# | B11 |
+-----+-----------------+-------------------+-----+
| A12 | A19 | SmemRD# | B12 |
+-----+-----------------+-------------------+-----+
| A13 | A18 | IOWR# | B13 |
+-----+-----------------+-------------------+-----+
| A14 | A17 | IORD# | B14 |
+-----+-----------------+-------------------+-----+
| A15 | A16 | DACK3# | B15 |
+-----+-----------------+-------------------+-----+
| A16 | A15 | DRQ3 | B16 |
+-----+-----------------+-------------------+-----+
| A17 | A14 | DACK1# | B17 |
+-----+-----------------+-------------------+-----+
| A18 | A13 | DRQ1 | B18 |
+-----+-----------------+-------------------+-----+
| A19 | A12 | REFR# | B19 |
+-----+-----------------+-------------------+-----+
| A20 | A11 | BClock | B20 |
+-----+-----------------+-------------------+-----+
| A21 | A10 | IRQ7 | B21 |
+-----+-----------------+-------------------+-----+
| A22 | A9 | IRQ6 | B22 |
+-----+-----------------+-------------------+-----+
| A23 | A8 | IRQ5 | B23 |
+-----+-----------------+-------------------+-----+
| A24 | A7 | IRQ4 | B24 |
+-----+-----------------+-------------------+-----+
| A25 | A6 | IRQ3 | B25 |
+-----+-----------------+-------------------+-----+
| A26 | A5 | DACK2# | B26 |
+-----+-----------------+-------------------+-----+
| A27 | A4 | TC | B27 |
+-----+-----------------+-------------------+-----+
| A28 | A3 | BALE | B28 |
+-----+-----------------+-------------------+-----+
| A29 | A2 | +5v | B29 |
+-----+-----------------+-------------------+-----+
| A30 | A1 | OSC | B30 |
+-----+-----------------+-------------------+-----+
| A31 | A0 | GND | B31 |
+-----+-----------------+-------------------+-----+

Note: some modem models are designed
to be connected to a long (16-bit)
ISA slot. They can be easily connected
into a short slot when using
interrupts in the range IRQ1..IRQ7.

From Sergey Kachalov To All 6 October 2002

KF> Kondratiev circuit <--> pisish multicard <--> modem.

KF> The internal modem is connected directly to the computer bus via
KF> a special adapter that converts the address on the address bus
KF> Spectrum into the modem address on the ISA connector and buffers the signals.
...........

I meant the external modem (Hardware, Com, I don’t know what else you can
call it!!!)

From Sergey Kachalov To All 8 October 2002

KF> Kondratiev circuit <--> pisish multicard <--> modem.

KF> The internal modem is connected directly to the computer bus via
KF> a special adapter that converts the address on the address bus

Yes, I want to cut off EXT!!! modem!!!

From Kirill Frolov To All 9 October 2002

KF>> The internal modem is connected directly to the computer bus via a
KF>> special adapter that converts the address on the Spectrum address bus
KF>> into the modem address on the ISA connector and buffers the signals.

From Oleg Groskow To All 9 October 2002

SK> ...........
SK> I meant an external modem (Hardware, Com, I don’t know what else to call it
SK>!!!)
What are they talking to you about? About the helicopter?
Read the facts _carefully_, if you haven’t caught up, you can smoke them.

Best regards, Oleg. [ZX]

From Alexandr Skoropisov To All 12 October 2002

SK> Yes, I want to cut EXT!!! modem!!!
The path from the external modem to the spec is through the multicard from the PC and the assembled
Kondratiev circuit.

May _Speccy_ be with you, Sergey!

... GUY Must _DIE_!!! =:E~E~~~
[ARIA] [ZX.SPECTRUM] [386+DOS] [500:572/16.33@ZXNet] [sk...@pisem.net]

From Kirill Frolov To All 12 October 2002

KF>> The internal modem is connected directly to the computer bus via
KF>> a special adapter that converts the address on the address bus

From Igor Turashev To All 12 October 2002

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
SK> Yes, I want to cut EXT!!! modem!!!
can you read? What does it say on the top line? internal
connects without a multicard, external - through it.

...bye.Sergey! ...tigrr//bw::ceg
... LTJ Bukem - Rhodes To Freedom ...

From Oleg Groskow To All 12 October 2002

SK> Yes, I want to cut EXT!!! modem!!!
Don’t you want an elephant?
How many more times do I have to explain this to you? What exactly doesn’t get to you?

Best regards, Oleg. [ZX]