WebEE

In Use
The control software is shown in Listing 3 and is suitable for an IBM PC or compatible machine running BASICA, G.W.BASIC or QBASIC. This software is about the minimum required to make sensible use of the programmer. section.

If BASICA or G.W.BASIC is being used, the program will run fairly slowly. This is a limitation of interpreted BASIC. QBASIC supplied with MS-DOS 5 is a much more advanced product and a good deal better in this respect.

Additional (faster) software is supplied on the disk available from the author (downloadable from this website).

An EPROM must not be inserted or removed if the "Program" or "Read" LED is lit, or if the programmer is configured for a different type of device. 24 pin EPROM's must be fitted in the lower pins (3-26) of the socket. In all cases pin 1 is upwards. Failure to observe the above may result in damage to the EPROM or (less likely) the programmer.

The programmer should be switched on and connected to COM1 (RS232 serial port 1) on the computer. Start the software and the "Program" LED will light. Once successful communication has been established the program will request information about the type of EPROM and the programming method required. See the table below or consult the manufacturers data book.

EPROM	Programming	Supply	Programming
Type Number	Voltage	Voltage	Pulse Length
2716 & 27C16	25V	5V	40mS
2732 & 27C32	21V	5V	40mS
2764	21V	5V	1mS
27C64 & 2764A	12.5V	5V	1mS
27128	21V	5V	1mS
27C128 & 27128A	12.5V	5V	1mS
27256 & 27C256	12.5V	6V	1mS
27512 & 27C512	12.5V	6V	1mS

 

Some 2764 and 27128 types require a complex arrangement of programming pulses however a single 1mS pulse will usually suffice. If in doubt or if problems are experienced use 40mS. Although some 2716 and 2732 devices will program successfully with a 1mS programming pulse, this is not recommended for final EPROM's, but may prove useful when testing software etc.

The use of the "A" suffix on 12.5V 2764 and 27128 types appears to be less than standard, it is suggested that all 2764's and 27128's should be tried on 12.5V first, since 21V will destroy a 12.5V device.

Once these selections have been made the "Program" LED will extinguish and the main menu will appear.

"Read" (menu option 1) reads the contents of an EPROM to a file. Note that the file format used is non-standard, however programs to convert to and from the Intel-HEX standard are given in Listings 4 and 5. The advantage of the file format is that it is easy to generate and edit manually.

"Program" (option 2) programs the EPROM from a file. The EPROM is not blank checked before programming or verified afterwards, these operations should be done from the main menu individually if required.

"Verify" (option 3) compares the contents of the EPROM with a file, and "Blank Check" (option 4) does as it's name suggests! Both these options report the number of locations that failed.

"Change Configuration" (option 5) re-starts the software so the EPROM type and programming method can be changed.

"Adjust Voltages" (option 6) allows the programming voltages to be checked and adjusted if required.

Happy programming!