PR0FI 1 MEGABYTE!!! THIS IS REALITY!!! .IRON0
HI ALL! It's me ALEX again. I recently figured out the circuit
samples of memory chips in its PR0FI+ and solved it up to 1 mega-
bytes expand. It turned out to be very simple. Ruler assembly
of eight memory chips is carried out by the CAS signal. Total
PR0FI implements four such signals - CAS0, CAS1, CAS2,
CAS3. Each signal defines one line out of four.
The CAS signal is supplied to the 15th leg of the memory chips included in
ruler. The bottom line has a capacity of 25 kilobytes. If in com-
The computer has 4 lines installed, then the capacity is
1 megabyte (1024 kb). The standard in PR0FI is 2 lines, i.e. 512
kilobyte
Expansion is carried out in the following way: for all micros -
hem of one (not installed) ruler, bend the 15th leg and attack
transfer them to the installed
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ sandwich ruler board
▒ ▒ ▒ ▒ way. 15 feet of chips
───▒1 ▒▒▒▒ 1b▒─── connect with each other and ki-
▒ ▒ give the desired CAS signal.
───▒2 15▒─── CAS Using a test wired into
▒▒ ROM can be determined to work
───▒3 14▒─── ruler ability.
▒ ▒ If the test produces an error,
───▒4 13▒─── this does not mean that this
▒ ▒ The microcircuit is dead. Need-
───▒5 12▒─── but it’s good to solder its conclusions
▒ ▒ and if there is an error again, then
───▒b 11▒─── you can replace it.
▒ ▒ For debugging it is desirable
───▒7 10▒─── have a logic probe.
▒ ▒ Warning: for soldering
───▒8 9▒─── it is advisable to use
▒ ▒ soldering iron about 40 watts and obligatory
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ preferably with a grounded tip.
I have already expanded my memory to 768 kilobytes and am going to do
1 megabyte.
Are you familiar with the problem with the #FD port??? When PR0FI is released
button 0N/0FF problems begin with the port. 0excellent solution
suggested in SPECTR0F0N'e N17. With one free
element "AND" ("&")the problem is very easily solved.
On the bottom board PR0FI+ (I'm not sure if on other PR0FI
elements will match. I have PR0FI with black and white CP/M) there is a mi-
we take the microcircuit under the name LE1 (U43) and cut off its first leg
and throw it at the input of the free element “AND”. 11 leg U43 too
we throw “I” at the second input, and connect its output to the 9th leg
LI1 (U47). I found a free element on the Ub2 microcircuit.
The 12th and 13th legs are the entrance, the 11th leg is the exit.
U43 U47
┃ АDR1 3┌────┐1 9┌────┐8
┃─────────┤ 1 0──┬──Х─┬───┤ & ├────── C_СМR1
┃ АDR13 2│ │ │ │ 10│ │
┃─────────┤ │ │ │ ┌─┤ │
┃ └────┘ │ │ │ └────┘
┃ ┌────────────┘ │ │
┃ │ SV0B. ELEM.Ub2 │ │
┃ │ 12┌────┐11 │ │
┃ └────┤ & ├───────┘ │
┃ АDR15 13│ │ │
┃─────────┤ ││
┃ └────┘ │ U32
┃ I0RQ 12┌────┐13 │4┌────┐b
┃─────────┤ 1 0────────┴─┤ & 0────── S_SMR0
┃ WR 11│ │ 5│ │
┃─────────┤ │ ┌─┤ │
┃ └────┘ │ └────┘
┃ U43 │
┃ ADR1 12┌────┐13 │
┃─────────┤ 1 0─────────┘
┃ ADR15 11│ │
┃─────────┤┤ │
┃ └────┘
U43
NU V0T V PPINCIPE I VSYA D0PAB0TKA PR0FI+, 0 NED0STATKAH SHE-
MY READ IN SPESTR0F0NE N17.
I have a request for all users of PR0FI+, who can it be?
из вас есть шема оцветнения SP/M ??? If you eat, give it away
ee SN0R KANU и kogda я ee soberu ona srazu poyavitsya v nahoj
newspapers.ALEKH '9b
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