mc68hc901fn Freescale Semiconductor, Inc, mc68hc901fn Datasheet - Page 12

• Manufacturer Part Number: mc68hc901fn
• Description: Multi-function Peripheral
• Manufacturer: Freescale Semiconductor, Inc

Introduction
1.1 KEY FEATURES
The MFP performs many of the functions common to most microprocessor-based systems.
The resources available to the user include:
By incorporating multiple functions within the MFP, the system designer retains flexibility
while minimizing device count.
1.2 REGISTER PROGRAMMING
From a programmer's point of view, the versatility of the MFP may be attributed to its register
set. The registers are well organized and allow the MFP to be easily tailored to a variety
of applications. All of the 24 registers are also directly addressable which simplifies
programming. The register map is shown in Table 1-1.
1-2
HEX
0D
0B
0F
• Eight individually programmable I/O pins with interrupt capability
• 16-source interrupt controller with individual source enable and masking
• Four timers, two of which are multi-mode timers
• Single-channel full-duplex universal synchronous/asynchronous receiver-transmitter
01
03
05
07
09
11
13
15
(USART) which supports:
— asynchronous formats
— byte synchronous formats, with the addition of a polynomial generator checker
RS5
0
0
0
0
0
0
0
0
0
0
0
RS4
ADDRESS
0
0
0
0
0
0
0
0
1
1
1
BINARY
RS3
0
0
0
0
1
1
1
1
0
0
0
RS2
0
0
1
1
0
0
1
1
0
0
1
Table 1-1. MFP Register Map
MC68HC901 USER’S MANUAL
RS1
0
1
0
1
0
1
0
1
0
1
0
ABBREVIATION
GPDR
IMRA
IMRB
IERA
IERB
IPRA
IPRB
ISRA
ISRB
AER
DDR
General Purpose I / O Data Register
Active Edge Register
Data Direction Register
Interrupt Enable Register A
Interrupt Enable Register B
Interrupt Pending Register A
Interrupt Pending Register B
Interrupt In-service Register A
Interrupt In-service Register B
Interrupt Mask Register A
Interrupt Mask Register B
REGISTER NAME
MOTOROLA