Dr. Scott M. Baker Page
Vintage
MIDI: Roland MT-32, Roland SC-55, HardMPU, and an Xi 8088
PS2-TTL
Serial Adapter for RC2014 and MIDI
Roland MT-32 Service Notes 1st ed.
Roland MT-32 Service Notes 3rd ed.
Ultimate
Roland MT-32 Tutorial (Phil's Computer Lab)
Serial
Port Controller, HITR Page 235 physical (Oct 1990)
Serial controller Types
- Type 1 appears identical to the serial portion of the IBM
PC AT Serial/Parallel Adapter.
- Type 2 incorporates all functions of Type 1 and also
supports FIFO mode.
- Type 3 incorporates all functions of Type 2 and provides
DMA mode.
- Type 4 incorporates all functions of Type 3 and provides
additional I/O addresses.
Note: Some systems using
the Type 2 controller do not support the FIFO mode. For
information about individual systems refer to the
system-specific technical reference manuals.
Note: Do not exceed
19.2K Baud with Type 1 and Type 2 Serial Controllers. In
short, older PS/2s can't reach the serial Baud rate needed
[parallel is something else].
31,250 baud directly supported on Types 3 and 4 using the
High Frequency Mode, divisor of 22 [decimal]. Percentage of
error Difference between Desired and Actual 0.538
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