30-pin SIMMs
Standard sizes: 256 KB, 1 MB, 4 MB, 16MB
30-pin SIMMS have 12 address lines, which can provide a total of 24 address bits. With an 8 bit data width, this leads to an absolute maximum capacity of 16 MB for both parity and non-parity modules (the additional redundancy bit chip usually does not contribute to the useful capacity).
| Pin # | Name | Signal Description | Pin # | Name | Signal Description | |
|---|---|---|---|---|---|---|
| 1 | VCC | +5VDC | 16 | DQ4 | Data 4 | |
| 2 | /CAS | Column Address Strobe | 17 | A8 | Address 8 | |
| 3 | DQ0 | Data 0 | 18 | A9 | Address 9 | |
| 4 | A0 | Address 0 | 19 | A10 | Address 10 | |
| 5 | A1 | Address 1 | 20 | DQ5 | Data 5 | |
| 6 | DQ1 | Data 1 | 21 | /WE | Write Enable | |
| 7 | A2 | Address 2 | 22 | VSS | Ground | |
| 8 | A3 | Address 3 | 23 | DQ6 | Data 6 | |
| 9 | VSS | Ground | 24 | A11 | Address 11 | |
| 10 | DQ2 | Data 2 | 25 | DQ7 | Data 7 | |
| 11 | A4 | Address 4 | 26 | QP* | Data parity out | |
| 12 | A5 | Address 5 | 27 | /RAS | Row Address Strobe | |
| 13 | DQ3 | Data 3 | 28 | /CASP* | Parity Column Address Strobe | |
| 14 | A6 | Address 6 | 29 | DP* | Data parity in | |
| 15 | A7 | Address 7 | 30 | VCC | +5VDC |
* Pins 26, 28 and 29 are not connected on non-parity SIMMs.
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