SIMM to Spectrum

Hello All.

More than once the question has arisen about
connecting SIMM to ZX-Spectrum.
I am throwing out information about 30-pin SIMM for everyone.

30-pin SIMM (SIPP)

│ N pin │ name │ N pin │ name │

│ 1 │ +5v │ 16 │ D4 │
│ 2 │ CAS │ 17 │ MA8 │
│ 3 │ D0 │ 18 │ MA9 │
│ 4 │ MA0 │ 19 │ MA10 │
│ 5 │ MA1 │ 20 │ D5 │
│ 6 │ D1 │ 21 │ WE │
│ 7 │ MA2 │ 22 │ GND │
│ 8 │ MA3 │ 23 │ D6 │
│ 9 │ GND │ 24 │ NC │
│ 10 │ D2 │ 25 │ D7 │
│ 11 │ MA4 │ 26 │ D8-out │
│ 12 │ MA5 │ 27 │ RAS │
│ 13 │ D3 │ 28 │ CAS-pr │
│ 14 │ MA6 │ 29 │ D8-in │
│ 15 │ MA7 │ 30 │ +5v │

All signals MAi, RAS, CAS, WE the same
that are supplied to RU5 or RU7.
Data inputs and outputs in SIMM
are combined, therefore, if in the computer
DI and DO of RU5(7) chips are connected
together, then a buffer is not needed. If
they are separate, then when installing SIMM
it is necessary to install an additional
buffer between the processor data bus
and the SIMM data bus.

In the computer circuit.
┌───────────────── from DI Z80
│ RU5(7)
│┌──┬───┬──┐
└──┤DI│ │DO├──── на буфер
├──┤ │ │
┌──┤WE│ │ │
│
└───────────────── сигнал
записи
Подключение SIMM
555АП5
┌──┬───┬──┐
┌────oOE│ │ │
│ ├──┤ │ │
│ │..│ │..│
│ ┌──┤DI│ │DO├─┐
│ │ └──┴───┴──┘ │
│ └──────────────── от DI Z80
│ ┌──────────────┘
│ │ SIMM
│ │ ┌──┬───┬──┐
│ └──┤DI│ │DO├─── на буфер
│ │..│ │... multiplexed
addresses are similar to RU5(7) addresses.
256k SIMM - MA9, MA10 are not connected
1Mb SIMM - MA10 is not connected
4Mb SIMM - all addresses are connected
When connecting a SIMM, remember that the memory must be regenerated, i.e. every few milliseconds
data must be selected from all
columns. This can be achieved
by flipping processor addresses
and video circuits on multiplexers
RAM address.

Sincerely,Ivan

گ‘’چچ َ خد×ظح ادؤدح, Ivan ! چچ’‘گ
ëجءسسخد ر سءح سإآر ذدعؤpء×ةج ! ;-)=

چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ گ‘’چ’‘گ
ëداؤء-شد, Sunday December 28 1997 02:47, Ivan Mak ذةسءج ؤجر All:

IM> ًدؤثجہقإخةإ SIMM
IM> 555لً5
IM> ‚€€ˆ€€€ˆ€€ƒ
IM> ‚€€€€oOEپ پ پ
IM> پ †€€‡ پ پ
IM> پ پ..پ پ..پ
IM> پ ‚€€‡DIپ پDO†€ƒ
IM> پ پ „€€‰€€€‰€€… پ
IM> پ „€€€€€€€€€€€€€€€€ دش DI Z80
IM> پ ‚€€€€€€€€€€€€€€…
IM> پ پ SIMM
IM> پ پ ‚€€ˆ€€€ˆ€€ƒ
IM> پ „€€‡DIپ پDO†€€€ خء آصئإز
IM> پ پ..پ پ..پ
IM> پ †€€‡ پ پ
IM> پ پ پ پ پ
IM> †€€€€‡WEپ پ پ
IM> پ
IM> „€€€€€€€€€€€€€€€€€€ سةاخءج
IM> عءذةسة
Sorry.. ْؤإسر دغةآدقثء ×ظغجء. Hءؤد شءث.

ًدؤثجہقإخةإ SIMM
555لً5
‚€€ˆ€€€ˆ€€ƒ
‚€€€€oOEپ پ پ
پ †€€‡ پ پ
پ پ..پ پ..پ
پ ‚€€‡DIپ پDO†€ƒ
پ پ „€€‰€€€‰€€… پ
پ „€€€€€€€€€€€€€€€€ دش DI Z80
پ پ
پ SIMM پ
پ ‚€€ˆ€€€ˆ€€ƒ پ
پ پ پ پDi†€‰€ خء آصئإز
پ پ..پ پ..پ
پ †€€‡ پ پ
پ پ پ پ پ
†€€€€‡WEپ پ پ
پ
„€€€€€€€€€€€€€€€€€€ سةاخءج
عءذةسة

گ‘’چچ َ ص×ءضإخةإح, Ivan چچ’‘گ

TR-DOS 5.04Ei