MC68HC58 Motorola, MC68HC58 Datasheet - Page 19

• Manufacturer Part Number: MC68HC58
• Description: Data Link Controller
• Manufacturer: Motorola

2.1.1.4 DATA[7:0] — DLC Data Bus
2.1.1.5 ECLK — 6800 Bus Clock
2.1.1.6 INT — DLC Interrupt Request
2.1.1.7 LITO — Logic In Transceiver Out
2.1.1.8 LOAD — External Bus Load
2.1.1.9 LOTI — Logic Out Transceiver In
2.1.1.10 OSC1, OSC2 — External Oscillator
2.1.1.11 PRLMD — Parallel Mode
2.1.1.12 PSEN — Power Supply Enable
MC68HC58
TECHNICAL DATA
These pins are the bidirectional data lines used to transfer parallel bytes to and from
the DLC. The data lines are in high-impedance state unless CS is asserted.
This pin is used to input a 6800 peripheral bus clock. Clock timing controls parallel data
exchange with the MCU. M68HC11, M68HC16, and M68300 MCUs all provide clock
outputs to facilitate connection of 6800-timed peripherals.
This pin is used to output an open drain active-low interrupt request signal to the MCU.
The signal is fully compatible with M68HC11, M68HC16, and M68300 interrupt re-
quest inputs. INT must have an external pull-up resistor.
This pin is an external tap on the internal receive signal sent from the transceiver to
the control logic. It is used for testing only, and must be left unconnected for normal
operation.
This pin provides an internal ground connection for the SAE J1850 multiplex bus load
resistor. If DLC analog ground is lost, LOAD goes to a high-impedance state.
This pin is an external tap on the internal transmit signal sent from the control logic to
the transceiver. It is used for testing only, and must be left unconnected for normal op-
eration.
The DLC can operate with either an external clock signal or an external ceramic res-
onator. These pins support connection of both types of clock. If an external clock
source is used, the signal is input via OSC1, and OSC2 is left floating. If a resonator
is used, it is connected between OSC1 and OSC2.
This pin is used to select the desired MCU interface mode. When this pin is pulled up
to V
This pin provides an external V
impedance state when the DLC is in standby mode.
DD
, the parallel mode is selected.
SIGNAL AND PIN DESCRIPTIONS
BATT
source when the DLC is active. It assumes high-
MOTOROLA
2-3