8.2Serial Ports
Prometheus contains 4 serial ports. Each port is capable of transmitting at speeds of up to 115.2Kbaud. Ports COM1 and COM2 are built into the ZF Micro CPU chip. They consist of standard 16550 type UARTs with
The serial ports use the following default system resources:
Port | Address range | IRQ |
COM1 | I/O 3F8 – 3FF | 4 |
COM2 | I/O 2F8 – 2FF | 3 |
COM3 | I/O 3E8 – 3EF | 4 |
COM4 | I/O 2E8 – 2EF | 3 |
The settings of COM1 and COM2 may be changed in the system BIOS. Select the Advanced menu, then I/O Device Configuration. Serial Port A is COM1, and Serial Port B is COM2. The base address and interrupt level may be modified on this page.
The settings of COM3 and COM4 may be changed using a different procedure:
The addresses of these two ports are selected on the Advanced menu of the BIOS. Select Advanced Chipset Control, then ISA I/O Chip Select Setup. I/O Window – io_cs1 is for COM3 and I/O window – io_cs2 is for COM4. The only parameter that may be changed is the address. The other settings must remain in their default values:
Window state: | Enabled |
Base Address: | (user selectable) |
Read/Write control: | Read/Write |
Window data width: | |
Active Level: | Active Low |
Window size: | 08 |
After making any desired changes, go to the
The interrupt (IRQ) settings for COM3 and COM4 are selected with J10. COM3 may use IRQ4 or IRQ9. COM4 may use IRQ3 or IRQ15. If both serial ports share the same IRQ, they may share IRQ4 or IRQ5. See page 16 for serial port IRQ jumper settings.
8.3Parallel Port
The parallel port (LPT1) is an
Port | Mode | Address range | IRQ | DMA |
LPT1 | ECP | I/O 378 – 37F | 7 | 3 |
The parallel port settings may be modified in the BIOS. Select Advanced menu, then I/O Device Configuration. The above four settings may then be modified.
Prometheus CPU User Manual V1.44 | Page 27 |