Zilog Z80230 - Manual (Page 271)

SCC/ESCC
User Manual
UM010903-0515 Application Notes
264
can be interconnected for communication between on-board serial controllers, or they can be con-
nected to the user’s custom communications hardware on another board. As a third option, they
can be connected to three on-board serial interfaces via the connector blocks labelled J13 through
J15.
Two of the on-board serial interfaces use EIA-RS-232 signal levels and pin arrangement. 25-pin D
connectors J1A or J2A are configured as DTE, while J1B and J2B are configured as DCE. These
serial interfaces are used by connecting one of the J5-J10 to J13 or J14, respectively. J1B is typi-
cally used for connection to the user’s PC or terminal.
The third on-board serial interface uses EIA-422 signal levels on connector J3A, J3B, or J4 and is
used by connecting one of J5-J10 to J15. The 25-pin D connector J3A uses the DTE pin arrange-
ment put forth in the EIA-530 standard. J3B is a DCE version of EIA-530, while the 8-pin circular
DIN connector, J4, is compatible with the Apple Macintosh Plus and later Macintoshes, and thus
with AppleTalk/LocalTalk equipment.
Table and Table summarize the serial interface connectors
.
The pin-out of the J5-J10 connectors is consistent, but may not be identical because of differences
among the various serial controllers. These differences are listed in Table .
Controller Port Connectors
Serial Controller Channel w/on/off Board Hardware Connect to this (these) Connector Blocks
(E)SCC Channel A J5
(E)SCC Channel B J6
ISCC Channel A J7
ISCC Channel B J8
IUSC J9 (J11 for Port pins)
(M)USC J10 (J12 for MUSC Port pins or USC
Channel B
On-Board Line Driver/Receiver Connectors
Using a Serial Chip Controller w/following on-chip Serial
Interface Connect Connectors in Table 6 to:
J1A or J1B EIA-RS-232 Console J13
J2A or J2B EIA-RS-232 J14
RS-422 Differential: J3A or J3B EIA-530 or J4 Circular-8 (DIN) J15