Motorola M68MPB334, Руководство пользователя

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MEVB SUPPORT INFORMATION
M68MPB334UM/D 4-7
Table 4-7. Logic Analyzer Connector J13 Pin Assignments (continued)
Pin Mnemonic Signal
7 DS DATA STROBE – Active-low output signal. During a
read cycle, indicates that an external device should
place valid data on the data bus. During a write cycle,
indicates that valid data is on the data bus.
8 BR /
CS0
BUS REQUEST – Active-low input signal that indicates
an external device requires bus mastership.
CHIP SELECT 0 – Output signal that selects peripheral
or memory devices at programmed addresses.
9 BG /
CS1
BUS GRANT – Active-low output signal that indicates
the MCU has relinquished the bus.
CHIP SELECT 1 – Output signal that selects peripheral
or memory devices at programmed addresses.
10 CSBOOT BOOT CHIP SELECT – An active-low output chip
select for external boot startup ROM
11 CLKOUT SYSTEM CLOCK OUTPUT – MCU internal clock
output signal.
12 A23 /
CS10
ADDRESS BUS BIT 23 – One bit of the 24-bit address
bus.
CHIP SELECT 10 – Output signal that selects
peripheral or memory devices at programmed
addresses.
13 A22 /
CS9
ADDRESS BUS BIT 22 – One bit of the 24-bit address
bus.
CHIP SELECT 9 – Output signal that selects peripheral
or memory devices at programmed addresses.
14 A21 /
CS8
ADDRESS BUS BIT 21 – One bit of the 24-bit address
bus.
CHIP SELECT 8 – Output signal that selects peripheral
or memory devices at programmed addresses.
15 A20 /
CS7
ADDRESS BUS BIT 20 – One bit of the 24-bit address
bus.
CHIP SELECT 7 – Output signal that selects peripheral
or memory devices at programmed addresses.