The following details the procedure for programming an EPROM using an IBM PC clone as a terminal connected to the PROMPRO - 8X. Note that contents to be programmed may either be entered manually or by downloading a .s19 file. However, prior to download ing a .s19 file it is suggested that you understand how to modify manually and perform the exercise in this tutorial.
In the optional exercise, and most associated projects use the INTEL 2716 PROM. Note that Intel designates their memory such that the user has some idea of what the device does. The 27 indicates an EPROM. Subsequent digits indicate the number of kbits of memory in the device. For example a 2716 is nominally 16k (2K 8-bit words) and a 27128 is 128k (16k 8-bit words). Note that the addresses of the 2716 range from 0x0000 - 0x07ff. (0x is used to indicate "hex").
This series of EPROMs are erased by exposing them to high intensity ultraviolet radiation for 20 minutes. The Computer Engineering Lab has one independent stand alone uV unit.
Erasure of a PROM results in logic ones being written in every location. Programming then is writing a zero into the appropriate locations. This has always struck me as the reverse of what make sense; much like having an erasure that blackens the paper and then writing with a white pencil, but that's life.
The PROMPRO-8X contains 128 kbits of volatile RAM. Using the terminal, you may view, edit, move, verify and do a number of other things with this data. (You are not using any of the memory or calculating power of the PC itself. The PC is simply being u sed as a 'dumb' terminal). Once the data in the 8X is what you desire, you may program (or 'burn') the PROM.
You should have first erased a PROM. Be certain the PROM is a 2716. Place it in the smaller Zero Insertion Force Socket, being very careful to align pin 1 on the device with the pin 1 on the socket.
Turn on power to the PROMPRO 8X. You should here the unit beep. If not, hit the reset button.
From the root directory of the PC, change directories to PROM; i.e., cd c:\prom. Execute file sdpc (Software Driver from PC). You will be greeted with a number of successive prompts;
The following is a discussion of a number of commands which are relevant.
Note that this command permits you to enter specific data into locations. An example of its use is X0000 which will cause the content of location 0x0000 to be displayed.
0000 FF, 0001 FE, 0002 FD, 0003 FC
0004 FB, 0005 FA, 0006 F9, 0007 F8
0008 F7, 0009 F6, 000A F5, 000B F4
000C F3, 000D F2, 000E F1, 000F F0
0400 00, 0401 10, 0402 20, 0403 30
0404 40, 0405 50, 0406 60, 0407 70
0408 80, 0409 90, 040A A0, 040B B0
040C C0, 040D D0, 040E E0, 040F F0
Note that we currently have may only have one PROM programmer. Please budget your time so as to avoid stacking on this machine ten minutes before the project is due.
If the machine should lock-up, the following procedure is recommended.
1. Attempt to reset using /R.
2. Try to reset using the Reset push button on the PROMPRO.
3. If all else fails, momentarily turn off the PROMPRO and reboot the PC. Note that the memory in the PROMPRO is volatile and your data will be lost when you turn off power to the PROMPRO. In practice I have found that it will not lockup unless I did something foolish.