Acronym for electrically programmable read-only memory, a type of integrated circuit read-only memory which can be reused by removing the chip from the computer, erasing its contents, electrically writing new data into it, and replacing it in the computer. EPROMs are more widely used than the related EAROMs.
EPROMs come in several sizes both in physical packaging as well and storage capacity
| EPROM Type | Size — bits | Size — bytes | Length (hex) | Last address (hex) |
|---|---|---|---|---|
| 1702, 1702A | 2 Kibit | 256 | 100 | 000FF |
| 2704 | 4 Kibit | 512 | 200 | 001FF |
| 2708 | 8 Kibit | 1 KiB | 400 | 003FF |
| 2716, 27C16 | 16 Kibit | 2 KiB | 800 | 007FF |
| 2732, 27C32 | 32 Kibit | 4 KiB | 1000 | 00FFF |
| 2764, 27C64 | 64 Kibit | 8 KiB | 2000 | 01FFF |
| 27128, 27C128 | 128 Kibit | 16 KiB | 4000 | 03FFF |
| 27256, 27C256 | 256 Kibit | 32 KiB | 8000 | 07FFF |
| 27512, 27C512 | 512 Kibit | 64 KiB | 10000 | 0FFFF |
| 27C010, 27C100 | 1 Mibit | 128 KiB | 20000 | 1FFFF |
| 27C020 | 2 Mibit | 256 KiB | 40000 | 3FFFF |
| 27C040 | 4 Mibit | 512 KiB | 80000 | 7FFFF |
| 27C080 | 8 Mibit | 1 MiB | 100000 | FFFFF |
NOTE: 1702 EPROMs were PMOS, 27x series EPROMs containing a C in the name are CMOS based, without the C are NMOS
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