Motorola M68MPB334 User Manual page 37

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