Zilog EZ80F91 - Manual (Page 32)

eZ80F91 Development Kit
User Manual
UM014220-0508 eZ80 Development Kit
27
Components P4, T1, C3, C4, and U11 provide the phone line interface to
the modem. On the eZ80Acclaim!
®
Development Kit, LEDs D1, D2, D3,
and D4 function as status indicators for this optional modem.
The phone line connection for the modem is for the United States only.
Connecting the modem outside of the U.S. requires modification.
7 D2 RxD indicator; can drive an LED anode without additional circuitry
8 D3 DTR indicator; can drive an LED anode without additional circuitry
9 D4 TxD indicator; can drive an LED anode without additional circuitry
Table 13. Connector J1
Pin Symbol Description
2 MOD_DIS Modem disable, active Low
4 V
CC
+5 VDC or +3.3 VDC input
24 GND Ground
25 PC4_DTR1 DTR interface; TTL levels
26 PC6_DCD1 DCD interface; TTL levels
27 PC3_CTS1 CTS interface; TTL levels
28 PC5_DSR1 DSR interface; TTL levels
29 PC7_RI1 Ring Indicator interface; TTL levels
30 PC0_TXD1 TxD interface; TTL levels
31 PC1_RXD1 RxD interface; TTL levels
32 PC2_RTS1 RTS interface; TTL levels
Table 12. Connector J9 (Continued)