mc68hc916y3 Freescale Semiconductor, Inc, mc68hc916y3 Datasheet - Page 326

• Manufacturer Part Number: mc68hc916y3
• Description: Mc68hc16y3 16 Bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

14.6.2.3 Host Sequence Registers
14.6.2.4 Host Service Registers
14.6.2.5 Channel Priority Registers
14.6.3 Development Support and Test Registers
14-18
MOTOROLA
The host sequence field selects the mode of operation for the time function selected
on a given channel. The meaning of the host sequence bits depends on the time func-
tion specified. Refer to Table 14-5, which is a summary of the host sequence and host
service request bits for each time function. Refer to the TPU Reference Manual
(TPURM/AD) and the Motorola TPU Literature Package (TPULITPAK/D) for more
information.
The host service request field selects the type of host service request for the time func-
tion selected on a given channel. The meaning of the host service request bits is de-
termined by time function microcode. Refer to the TPU Reference Manual (TPURM/
AD) and the Motorola TPU Literature Package (TPULITPAK/D) for more information.
A host service request field of %00 signals the CPU that service is completed and that
there are no further pending host service requests. The host can request service on a
channel by writing the corresponding host service request field to one of three non-
zero states. It is imperative for the CPU to monitor the host service request register
and wait until the TPU2 clears the service request for a channel before changing any
parameters or issuing a new service request to the channel.
The channel priority registers (CPR1, CPR2) assign one of three priority levels to a
channel or disable the channel. Table 14-5 indicates the number of time slots guaran-
teed for each channel priority encoding.
These registers are used for custom microcode development or for factory test. De-
scribing the use of these registers is beyond the scope of this manual. Register de-
scriptions are provided in D.10 Time Processor Unit 2 (TPU2). Refer to the TPU
Reference Manual (TPURM/AD) for more information.
CHX[1:0]
00
01
10
11
Freescale Semiconductor, Inc.
Table 14-5 Channel Priority Encodings
For More Information On This Product,
TIME PROCESSOR UNIT 2
Go to: www.freescale.com
Disabled
Service
Middle
High
Low
Guaranteed Time Slots
1 out of 7
2 out of 7
4 out of 7
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MC68HC16Y3/916Y3
USER’S MANUAL