TC11IB Datasheet, PDF (23/108 Pages) Infineon Technologies AG – 32-Bit Single-Chip Microcontroller

TC11IB
Table 1
Symbol
CKE
MR/W
HOLD
HLDA
Pin Definitions and Functions(cont’d)
Pin In PU/ Functions
Out PD¹⁾
P26 O PUC EBU_LMB SDRAM Clock Enable Output
C21 O PUC EBU_LMB Motorola-style Read / Write Output
C22 I
PUC EBU_LMB Hold Request Input
In External Master Mode:
While HOLD is high, Tricore is operating in normal
mode (is owner of the external bus). A high-to-low
transition indicates a hold request from an external
master.Tricore backs off the bus and activates HLDA
and goes into hold mode.
A low-to-high transitions causes an exit from hold
mode.Tricore deactivates HLDA and takes over the
bus and enters the normal operation again.
In External Slave Mode:
While both HOLD and HLDA are high, Tricore is in
hold mode, the external bus interface signals are
tristated. When Tricore is released out of hold mode
(HLDA =0) and has completely taken over control of
the external bus, a low level at this pin requests Tri-
core to go into hold mode again. But in any case Tri-
core will perform at least one external bus cycle
before going into hold mode again.
A23 I/O PUC EBU_LMB Hold Acknowledge Input / Output
In External Master Mode:
OutPut. High during normal operation.When Tricore
enters hold mode, it sets HLDA to low after releasing
the bus. On exit of hold mode, Tricore first sets HLDA
to high and then goes onto the bus again (to avoid col-
lisions).
In External Slave Mode:
Input. A high-to-low transition at this pin releases Tri-
core from hold mode.
Data Sheet
19
V2.3, 2003-11