Processor Technology Sol-PC, Руководство пользователя

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V. SUBROUTINES
A. Introduction to the SOLOS Machine Language Interface
The Machine Language Interface with SOLOS is based on:
1. A predefined set of 'pseudo' I/O ports allowing
software compatibility as well as providing an easy
means of supporting any I/O device.
2. A system defined register usage when interfacing with
SOLOS.
3. A system jump table of entry points.
First are the pseudo ports. Built into SOLOS are four input and
four output pseudo ports. I/O requests made to a pseudo port are
converted internally to a request either to a specific device, a
built-in routine, or a user written routine. All non-tape I/O
requests made to SOLOS are made with reference to one of the
following pseudo ports.
PSEUDO PORTS FOR SOLOS
Pseudo
Port
Input Output
0 Keyboard VDM driver
1 Serial port Serial port
2 Parallel Port Parallel Port
3 User written routine User written routine
PSEUDO PORTS FOR CUTER
Pseudo
Port
Input Output
0 Keyboard data from VDM driver
parallel port 3,not KDR
status, on port 0; bit 0.
1 Serial port 1, RDA Serial port 1, TBE status on
status on port 0, bit 6. port 0, bit 7.
2 Parallel port 2 with not- Parallel port 2 with not-PXDR
PDR status on port 0, bit status on port 0, bit 1.
2.
3 User written routine. User written routine.
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