MC68HC58 Motorola, MC68HC58 Datasheet - Page 33

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

2.6 Reset
MC68HC58
TECHNICAL DATA
While the RST signal is asserted, the DLC is held in an inactive state. The DLC is ac-
tivated when the RST line goes high. When exiting the low-power standby mode, all
system power must be applied and stable at the time RST goes high in order for the
DLC to be properly activated. During reset, all data in the DLC FIFO buffers is lost.
Many MCUs have low-power standby modes that permit them to remain inactive until
needed. These devices typically exit low-power stop when reset, or when an interrupt
request is received. If the host MCU, as well as the DLC, are to be activated when the
DLC detects J1850 bus activity, use of a common reset line may cause the frame that
activates the system to be lost.
After the reset line goes high, the host MCU writes command and configuration bytes
to the DLC to initialize it. The “load as configuration byte – immediate” command
should be issued to initialize the DLC. The host may commence further operations with
the DLC (t
for more information on parameter specifics. Refer to SECTION 4 DATA LINK CON-
TROLLER OPERATION for more information on system initialization and configura-
tion.
con
) afterwards. Refer to APPENDIX A ELECTRICAL CHARACTERISTICS
SIGNAL AND PIN DESCRIPTIONS
MOTOROLA
2-17