MC68HCP11 Datasheet, PDF (6/45 Pages) Motorola, Inc – 8-Bit Microcontroller

PA7/PAI/OC1 1
PA6/OC2/OC1 2
PA5/OC3/OC1 3
PA4/OC4/OC1 4
PA3/OC5/OC1 5
PA2/IC1 6
PA1/IC2 7
PA0/IC3 8
PB7/A15 9
PB6/A14 10
PB5/A13 11
PB4/A12 12
PB3/A11 13
PB2/A10 14
PB1/A9 15
PB0/A8 16
PE0/AN0 17
PE1/AN1 18
PE2/AN2 19
PE3/AN3 20
VRL ₂₁
VRH ₂₂
VSS ₂₃
MODB/VSTBY 24
48 ^VDD
47 PD5/SS
46 PD4/SCK
45 PD3/MOSI
44 PD2/MISO
43 PD1/TxD
42 PD0/RxD
41 IRQ
40 XIRQ
39 RESET
38 PC7/A7/D7
37 PC6/A6/D6
36 PC5/A5/D5
35 PC4/A4/D4
34 PC3/A3/D3
33 PC2/A2/D2
32 PC1/A1/D1
31 PC0/A0/D0
30 XTAL
29 EXTAL
28 STRB/ R/W
27 E
26 STRA/AS
25 MODA/LIR
Figure 3 48-Pin DIP Pin Assignments
2 Operating Modes and Memory Maps
In single-chip operating mode, the MC68HC11A8 is a monolithic microcontroller without external ad-
dress or data buses.
In expanded multiplexed operating mode, the MCU can access a 64 Kbyte address space. The space
includes the same on-chip memory addresses used for single-chip mode plus external peripheral and
memory devices. The expansion bus is made up of ports B and C and control signals AS and R/W. The
address, R/W, and AS signals are active and valid for all bus cycles including accesses to internal mem-
ory locations. The following figure illustrates a recommended method of demultiplexing low-order ad-
dresses from data at port C.
MOTOROLA
6
MC68HC11A8
MC68HC11A8TS/D