-
Notifications
You must be signed in to change notification settings - Fork 12
/
schematic.txt
51 lines (43 loc) · 1.3 KB
/
schematic.txt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
Solder the 30-pin simm ram module pins to Arduino pins like detailed below :
30-pin SIMM Memory Module
Pin # Name Signal Description Arduino Pin
1 VCC +5 VDC +5 VCC
2 /CAS Column Address Strobe analog pin 0
3 DQ0 Data 0
4 A0 Address 0
5 A1 Address 1
6 DQ1 Data 1
7 A2 Address 2
8 A3 Address 3
9 VSS Ground GND
10 DQ2 Data 2
11 A4 Address 4
12 A5 Address 5
13 DQ3 Data 3
14 A6 Address 6
15 A7 Address 7
16 DQ4 Data 4
17 A8 Address 8
18 A9 Address 9
19 A10 Address 10
20 DQ5 Data 5
21 /WE Write Enable analog pin 1
22 VSS Ground
23 DQ6 Data 6
24 A11 Address 11
25 DQ7 Data 7
26 QP* Data parity out
27 /RAS Row Address Strobe analog pin 2
28 /CASP* Parity Column Address Strobe
29 DP* Data parity in
30 VCC +5 VDC
30-pin SIMM Memory Module Arduino
Address pin 0 to 5 (A0..A5) PORTB (digital pin 8..13)
Address pin 6 to 11 (A6..A11) GND
Data pin 0 to 7 (DQ0..DQ7) PORTD (digital pin 7..0) (in that order, DQ0-pin7, DQ1-pin6, DQ2-pin5...DQ7-pin0)
The others will be not connected.
This way you will address 6 bits for rows and 6 bits for columns.
Addresses space will be of 64rows x 64columns = 4096 addresses
1 byte each = 4KB of space.
If you need to use more RAM you can solder the 3 analog pins remaining
to simm ram module pins A6, A7 and A8. It will give you 256 KB of RAM space.