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68000 68030 CPLD FPGA ARM
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CP/M-68K
Running CP/M-68K with a Dual 6850 Board
 
If you have a 68681 Board - Click Here
 
To run CP/M-68K on the Mega-68000 Computer System you will require a system fitted with the following boards:
 
1x Memory-2 Board with NO ROM fitted thus JB1 position is n/a + J1 short (IC2 with gal8b firmware)
1x Memory-2 Board with NO ROM fitted thus JB1 position is n/a + J1 short (IC2 with gal8c firmware)
1x Memory-2 Board with ROM ADAPTER thus JB1 pins 3-4 short + J1 open (IC2 with gal8d firmware)
1x Dual 6850 Board with CON ACIA modification (Base Address: ACxxxx + J1 pins 1-2 short)
 
  For more details on the CON ACIA modification - see here:

Dual 6850/Mods

 
The System ROM that includes CP/M-68K is an STM M27C322 2M x 16 UV EPROM. The ROM resides in memory at C00000-FFFFFF
 
The very popular and inexpensive TL866A MiniPro Programmer was used here to program the System ROM. Before attempting to program the ROM with a TL866A check the following ...
 
App Software Ver: 6.85
Firmware Ver: 03.2.86
 
... and upgrade if necessary before proceeding.
 

Although not on the supported device list the TL866A MiniPro Programmer can be used to program STM M27C322 EPROM's using the AMD AM27C4096 programming algorithm. VPP Voltage should be set to 12.5V and Check ID must be un-checked.

 

A TL866A Programmer Adapter for 27C322 EPROM's similar to the one shown here is required. The adapter accepts the physically larger 27C322 device and routes the 27C322 signals to the correct pins on the TL866A's programming socket.

The 27C322 EPROM has 8x the capacity of a 27C4096 device and therefore the 27C322 must be programmed in 8 blocks of 512KB. The block or bank to be programmed is set on the Programmer Adapter, typically a binary code (000-111) set on DIP switches or the position (0-7) of a rotary switch will define this.

The System ROM binary image is split into 7 files, each file contains data for one bank of the 27C322 EPROM. The file name format is: #_system_rom_v2.0_27c322.bin - # indicates the bank number. Use the procedure below to program 7 of the 8 banks of the 27C322, bank 6 can be skipped as it contains no data.

 
Programming IC6
 
1. Download the following files:
 
7_system_rom_v2.0_27c322.bin   CP/M Disk B
6_system_rom_v2.0_27c322.bin   n/a (not required)
5_system_rom_v2.0_27c322.bin   CP/M Disk A 3/3
4_system_rom_v2.0_27c322.bin   CP/M Disk A 2/3
3_system_rom_v2.0_27c322.bin   CP/M Disk A 1/3
2_system_rom_v2.0_27c322.bin   CP/M BIOS
1_system_rom_v2.0_27c322.bin   CP/M OS
0_system_rom_v2.0_27c322.bin   System BIOS, Monitor, and BASIC
2. Launch the TL866A's Application Software (MiniPro Programmer)
3. Using the 'Select IC' button set the device type to AMD AM27C4096
4. Change VPP Voltage to 12.50V in 'IC Config Information'
5. Deselect Check ID in 'Options'
6. Insert a 27C322 part in the Programmer Adapter's ZIF socket
7. Goto Open(O) from the File(F) menu and browse in a #_system_rom_v2.0_27c322.bin file
8. Match the bank number on the Programmer Adapter to the bank number of the file
9. Goto Program(P) from the Device(D) menu
10. Click the 'Program' button
  'Programming Successful!' appears
11. Click the 'Cancel' button
12. Repeat steps 7-11 for each #_system_rom_v2.0_27c322.bin file
13. Remove the programmed 27C322
 
 
System ROM V1.0 files
 
1. Download the following files:
 
7_system_rom_v1.0_27c322.bin   CP/M Disk B
6_system_rom_v1.0_27c322.bin   n/a (not required)
5_system_rom_v1.0_27c322.bin   CP/M Disk A 3/3
4_system_rom_v1.0_27c322.bin   CP/M Disk A 2/3
3_system_rom_v1.0_27c322.bin   CP/M Disk A 1/3
2_system_rom_v1.0_27c322.bin   CP/M BIOS
1_system_rom_v1.0_27c322.bin   CP/M OS
0_system_rom_v1.0_27c322.bin   System BIOS, Monitor, and BASIC
 
 
Disclaimer
All hardware designs, software, and information shared on this website is provided "as is"
without warranty of any kind and strictly for personal non-commercial use only.
 
 
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