Logo SB180
The COMM-180-M/S, Modem/SCSI I/O Expansion Board
The COMM-180-M/S was built as an expansion board for the SB180. It mounts 'piggy-back' onto the SB180, connecting to the I/O Expansion header (J5).
The board was available in three configurations: the -M was Modem only, the -S was SCSI only, and the -M-S was both Modem and SCSI. All three configurations included all of the basic components of the board, only the Modem module or the SCSI chip was left out for the -M and -S versions.
The -M version uses a XECOM XE1203 MOSART (MOdem Synchronous Asynchronous Receiver Transmitter) module which is a complete Bell 103-212A compatable 300/1200 Baud modem. The module also provides DTMF (Dual Tone Multi-Frequency) encode/decode, and voice synthesis.
The -S version uses the NCR 5380 SCSI controller chip to provide access to SCSI harddisks and such.
The December 1985 issue of BYTE Magazine featured a long Circuit Cellar article about the Turn Key Bulletin Board System (TKBBS) running on the SB180 with a COMM-180-M providing the modem connection.
Header and Jumper Information
Click on picture for a larger image.

Click on picture for a larger image.

SB180 Home