Z85C3008VSG Datasheet, PDF (16/81 Pages) Zilog, Inc. – CMOS SCC Serial Communications Controller

CMOS SCC Serial Communications Controller
Product Specification
8
TxDA, TxDB
Transmit Data (outputs, active High) . These output signals transmit serial data at stan-
dard TTL levels.
TRxCA, TRxCB
Transmit/Receive Clocks (inputs or outputs, active Low) . These pins can be 
programmed in several different operating modes. TRxC may supply the receive clock or
the transmit clock in the input mode or supply the output of the Digital Phase-locked loop,
the crystal oscillator, the Baud Rate Generator, or the transmit clock in the output mode.
W/REQA, W/REQB
Wait/Request (outputs, open-drain when programmed for a Wait function, driven
High or low when programmed for a Request function) . These dual-purpose outputs
can be programmed as Request lines for a DMA controller or as Wait lines to synchronize
the CPU to the SCC data rate. The reset state is Wait.
Z85C30
The following links refer to descriptions of the pin functions specific to the Z85C30
device.
• A/B
• CE
• D7–D0
• D/C
• RD
• WR
A/B
Channel A/Channel B (input) . This signal selects the channel in which the Read or
Write operation occurs.
PS011706-0511
Pin Descriptions