MC68HC000EI20 Freescale Semiconductor, MC68HC000EI20 Datasheet - Page 83

• Manufacturer Part Number: MC68HC000EI20
• Description: IC MPU 16BIT 20MHZ 68-PLCC
• Manufacturer: Freescale Semiconductor

Specifications of MC68HC000EI20

• Processor Type: M680x0 32-Bit
• Speed: 20MHz
• Voltage: 3.3V, 5V
• Mounting Type: Surface Mount
• Package / Case: 68-PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

Figure 5-35 shows a synchronous read cycle and the important timing parameters that
apply. The timing for a synchronous read cycle, including relevant timing parameters, is
shown in Figure 5-36.
MOTOROLA
UDS/LDS
CLOCK
DTACK
DATA
ADDR
R/W
On the rising edge of the clock, at the end of S7 (which may be the start of
S0 for the next bus cycle), the processor places the address bus in the
high-impedance state. During a write cycle, the processor also places the
data bus in the high-impedance state and drives R/W high. External logic
circuitry should respond to the negation of the AS and UDS, LDS, and/or DS
by negating DTACK and/or BERR. Parameter #28 is the hold time for
DTACK, and parameter #30 is the hold time for BERR.
AS
M68000 8-/16-/32-BIT MICROPROCESSORS USER'S MANUAL
6
S0
18
Freescale Semiconductor, Inc.
Figure 5-35. Synchronous Read Cycle
For More Information On This Product,
S1
Go to: www.freescale.com
S2
9
S3
47
S4
S5
27
S6
S7
S0
5- 37