This are roughly translated parts of larger articles published in Remarks. There is no guarantee that the hardware project will work. Place the 27128 in one of the ROM IC sockets. Pin 2 of the 27128 must be connected with A12 likewise as was done to the 2764.Īt X3 now connect 1 to 16. The pins 1, 27 and 28 of the 27128 EPROM can easily be connected with each other and than to the +5V. So before hand bent out pin 26, and connect it by means of a piece of wire to Z35 pin 3 (A13). It's extremely difficult to disconnect the socket pin from the +5V. This pin should not go in the socket hole 24, because that one is connected to +5V. Also make sure that the connection 16 to 1 is broken.įor installation of a 27128 EPROM follow the same instructions as above (point 1-7) and furthermore change the following too: This metal covered hole (A12) is connected with Z51 pin 10 (A12) at the components side.Ĭonfirm that in jumper X3 the following connections exist: 9 to 8, 10 to 7 en 11 to 6. Pin 2 of the 2764 must now be connected with the metal hole right beneath pin 13 of Z34 (ROM B). Pin 14 of the 2764 should be placed at pin 12 of the IC socket.
#2764 EPROM PROGRAMMER INSTALL#
Install the EPROM's (the 2764 in Z33, the 2732 in Z34). Pin 21 of Z34 (ROM b) must now be connected with Z51 pin 6 (A11). This pin (was A11) now becomes CS* and stays low all the time. Pin 18 of Z34 (ROM B) is connected to A11 at the underside and this trace goes through a hole to the upper-side were it can easily be cut (ROM B, releasing pin 18 from A11)Īt point 1 we also interrupted the A12 trace so we have to fix this by reconnecting Z38 pin 5 (A12) with Z51 pin 10 (A12).Ĭonnect the metal hole at pin 18 of Z34 (ROM B) with GROUND, e.g. The following instruction is for replacing the ROM into EPROM on a American motherboard with modification "G".Ĭut through the print traces (under and upper-side of the main circuit board) at pin 21 of Z34 (ROM B, isolating pin 21 from A12) This is basically the same as the 2764 except that pin 26 has to be bent out at forehand as it will get the signal of A13 later on. Attach a piece of wire to pin 2 of the 2764 to connect it later on to A12 on the motherboard. So just connect these pins (1, 28, 27 and 26) with each other. Pin 26 of the 2764 already gets +5V as it corresponds with pin 24 of the ROM IC socket. Moreover the four extra pins (1, 2, 27 and 28) of the 2764 must be provide with the right signals. By placing the 2764 in the IC socket in such a way that pin 14 of the 2764 will match with pin 12 of the IC socket Z33, we accomplish that most part of the pins will be connected to the right signal.įrom the differences and similarities between the ICs one can conclude that the ROM IC socket on the motherboard will changes (get a other function) only at two places, pins 18 and 21. The pins 3 until 26 at the 2764 match, with exception of pins 20 and 23, with pins 1 until 24 of the ROM A. Pin 18 = CS (2732) in stead of A11 (ROM B) The differences between a ROM B (2332B) and a 2732 are: Pin 27 at the 2764 = PGM* only for programming Pin 1 at the 2764 = VPP, only for programming The differences between a ROM A (2364) and a 278 are: The IC sockets on the motherboard of a TRS-80 Model I are wired for the 2332B / 2364. Look at pin numbers and the signals from the (EP)ROM's. More information these issues, cookies and privacy can be read on the Privacy page.Examine the ROMs and EPROM above carefully. All data on this site is presented as is and visitors use it at their own risk. As such Niall O'Leary Services accepts no liability in respect of the accuracy of data on this website. The EPROM must not be inserted into or removed from a board with voltage applied to VPP. Note 2: VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP. Ein mikrocontrollerbasiertes Programmiergerät für EPROMs und EEPROMsĪll data on this site is derived from external sources, principally Europeana, but also Wikipedia. Programming Waveforms (Note 3) TL/D/103314 Note 1: National’s standard product warranty applies to devices programmed to specifications described herein. The study of radiation damage of EPROM 2764 memory Nr 5 - 6ĭigital Library of the Silesian University of Technology
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Programmsysteme einer Industrierobotersteuerung mit Mikrorechnerĭigital Mechanism and Gear Library - Europeana Intel® 27C64 CHMOS EPROM Memory Die, 1985 Swedish National Museum of Science and Technologyĭiagram of Erasable Programmable Read-Only Memory Chip (EPROM) and Corresponding Microchipĭiagram of Erasable Programmable Read-Only Memory Chip (EPROM)Įrasable Programmable Read-Only Memory (EPROM) Microchipįorgácsoló megmunkálás CNC vezérlésű szerszámgépen 1.
Comparison of gamma ray effects on EPROMs and E2PROMs