PROM Burning Chips for the PX-8 TN0037 To fully use the portability of the Geneva, there is a need to understand and create programmed chips for those ROM sockets used as drives B: and C:. The following method will explain how the data is formed and placed into a 2764 PROM. Similar techniques are used for larger ROMS. HARDWARE: QX-10 GTEK Model 7128 Prom Burner RS-232 cable Pin connections: QX-10 signal name GTEK 3------ transmit --<<<---2 2------ receive --->>>---3 5------ RTS -------<<<---4 4------ CTS ------->>>---5 7------ Gnd -------------7 6------ DTR -------<<<---20 Connectors: DB-25 MALE---------------DB-25 FEMALE (Signal names and direction are viewed from the GTEK end.) RS-232 Protocol: 300 baud, 8 bit word, 1 stop bit, no parity Xon/Xoff handshaking SOFTWARE: MODEM7.COM PROMFORM.COM The 7128 is a smart device and will auto-adjust to your selected baud rate. It also transmits back to you status of itself as well as type of rom selected. Documentation with the GTEK 7128 is very well done and gives a complete list of commands. (see GTEK manual) Because the data must be in HEX format and is easiest to burn into the prom using Intel Hex format, we need to convert each XXXXX.COM file to a more usable form with PROMFORM.COM. HEX format is accepted by the 7128 as a complete statement: :100A450045464748494A4B4C4D4E4F5051525354557E The colon prompt puts the 7128 into program mode. Complete explanation of the HEX format is in the GTEK manual. Sequence of operation: 1. Run SETUP.COM to verify / establish RS-232 protocol. 2. Run PROMFORM.COM to convert to Intel Hex file. a. It seemed appropriate to first burn PROMFORM.COM B. Run PROMFORM.COM on the QX-10, A>PROMFORM (sample menu) PROM format amd write program version 1.0 (c) by EPSON Press ESC to restart PROMFORM, STOP to exit. Function (1=format/write), 2=compare, 3=Rom capsule directory) ? select 1 (functions 2 & 3 are for the PX-8) ROM name (14 characters max.) ? PROMBURNER Version number (nn) ? 15 Date (mmddyy) ? 091084 (Above information is for identification only, can be anything.) Output device (1=FDD, 2=PROM writer, 3=microcassette) ? 1 PROM type (1=64Kx1, 2=64Kx2, 3=128Kx1, 4=128Kx2, 5=256Kx1, 6=256Kx2)? 1 Enter file names (31 directory max.) RETURN to end 1 PROMFORM.COM 2 (c/r) Max addr of ROM=1FFF top of data address=0080 tail of data address=067F Header: ROM name='PROMBURNER' VER. 1.5 date=09/10/84 PROM type=64Kx1 PROMFORM.COM (RETURN to proceed) Name of file to output ? PROM.HEX (this is the hex filename written back to the disk.) Output complete (You are now recycled to the menu of functions, use CTRL C to quit.) (Devices 2 & 3 are for PX-8, 1 will use the QX-10 logged disk drive.) (Prom types displayed don't match any numbers printed on the chips, the 2764 will work with 64x1, I haven't figured out exactly which proms are refered to by the other selections.) You will see proms marked such as: 2764, 27128, 27256 3. Run MODEM7.COM , i.e. A>MODEM7 T (c/r) a. Use spacebar a couple times to wake up the 7128 The GTEC MENU will display with: xxxx> b. Type M for menu of chips for selection. c. Select the desired type rom by letter input. In this case, E for 2764 d. 2764> is displayed. e. Raise the lever, insert the chip U notch toward the lever. Lower the lever to lock it in. f. Type CTRL T (modem will ask for filename) Type PROM.HEX g. The file will be sent and burned into the rom. When done, the 7128 will return to 2764> h. Raise the lever, remove and mount the chip in MOLEX chip carrier part number 8878. Orient with the U notch on the chip towards the double holes in the end tab, bend the pins around and inward to secure chip to carrier. 4. Your program PROMFORM.COM is now ready for use in the PX-8. 5. The GTEK also can output files in HEX format so we can save code to disk and re-burn roms, like the unused Skiwriter 2764's. 6. Roms known to be useable directly are: 2764, 27128, and 27256. (pinouts match inside the PX-8) 7. A handy prom eraser was also purchased from GTEK, Model DE-4 made by UVP inc. Total cost for burner and eraser was $521.00. GTEK phone number: (601) 467-8048 MOLEX phone number: (312) 969-4450 Jim Tetzlaff Epson Mid America