MC9S12A256 Motorola, MC9S12A256 Datasheet - Page 62

• Manufacturer Part Number: MC9S12A256
• Description: MC9S12DT256 Device User Guide V03.03
• Manufacturer: Motorola

MC9S12DT256 Device User Guide — V03.03
Figure 2-6 External Clock Connections (PE7=0)
EXTAL
CMOS-COMPATIBLE
EXTERNAL OSCILLATOR
(VDDPLL-Level)
MCU
XTAL
not connected
2.3.14 PE6 / MODB / IPIPE1 — Port E I/O Pin 6
PE6 is a general purpose input or output pin. It is used as a MCU operating mode select pin during reset.
The state of this pin is latched to the MODB bit at the rising edge of RESET. This pin is shared with the
instruction queue tracking signal IPIPE1. This pin is an input with a pull-down device which is only active
when RESET is low.
2.3.15 PE5 / MODA / IPIPE0 — Port E I/O Pin 5
PE5 is a general purpose input or output pin. It is used as a MCU operating mode select pin during reset.
The state of this pin is latched to the MODA bit at the rising edge of RESET. This pin is shared with the
instruction queue tracking signal IPIPE0. This pin is an input with a pull-down device which is only active
when RESET is low.
2.3.16 PE4 / ECLK — Port E I/O Pin 4
PE4 is a general purpose input or output pin. It can be configured to drive the internal bus clock ECLK.
ECLK can be used as a timing reference.
2.3.17 PE3 / LSTRB / TAGLO — Port E I/O Pin 3
PE3 is a general purpose input or output pin. In MCU expanded modes of operation, LSTRB can be used
for the low-byte strobe function to indicate the type of bus access and when instruction tagging is on,
TAGLO is used to tag the low half of the instruction word being read into the instruction queue.
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