Microcontroller User's Guide

USER’S GUIDE
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Read Access: Can be read anytime.
Write Access: Can be written when the RPC mode is enabled (RPCON=1).
RPCTL.1 RPCON
Enable the RPC 8042 I/O protocol. When set, port 0 becomes the data bus,
and port 2 becomes the control signals.
Initialization: Cleared on all resets.
Read Access: Can be read at any time.
Write Access: Can be written at any time.
RPCTL.0 RG0
This is a Range bit which is used to determine the size of the program
memory space. Its usage is shown above.
Initialization: Unaffected by watchdog, external, or power–up resets. Cleared on a No V
LI
reset or clearing of the security lock.
Read Access: Can be read at any time.
Write Access: Cannot be modified by the application software. Can only be modified via
the Bootstrap loader.
DS5001/DS5002 RPC STATUS REGISTER
Label: RPS Register Address: 0DAH
ST7 ST6 ST5 ST4 IA0 F0 IBF OBF
Bit Description:
RPS.7–4: General purpose status bits that can be written by the microcontroller and
can be read by the external host.
Initialization: Cleared when RPCON=0.
Read Access: Can be read by DS5001/DS5002 and host CPU when RPC mode is invoked.
Write Access: Can be written by the DS5001/DS5002 when RPC mode is invoked.
RPS.3: IA0
Stores the value of the external system A0 for the last DBBIN Write when
a valid write occurs (as determined by the IBF flag).
Initialization: Cleared when RPC=0.
Read Access: Can be read by DS5001/DS5002 and host CPU when in RPC mode.
Write Access: Automatically written when a valid DBBIN Write occurs. Cannot be written
otherwise.
RPS.2: F0
General purpose flag written by the DS5001/DS5002 and read by the
external host.
Initialization: Cleared when RPC=0.