PD780701Y_15 Datasheet, PDF (35/66 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCONTROLLER

µPD780701Y, 780702Y
4.8 IEBus Controller (µPD780702Y only)
The µPD780702Y incorporates an IEBus controller. The functions of the IEBus interface are limited compared
with those of previous models (i.e., those incorporated in the µPD78098B Subseries).
Table 4-4 shows a comparison of the interfaces in the µPD78098B Subseries and the µPD780702Y.
Table 4-4. IEBus Interface Comparison (µPD78098B Subseries and µPD780702Y)
Item
IEBus Incorporated in µPD78098B Subseries
IEBus Incorporated in µPD780702Y
Communication mode
Internal system clock
Mode 0, mode 1, mode 2
fX = 6.0 (6.29) MHz
Fixed at mode 1
fX = 6.291456 MHz^Note
Internal buffer size
Transmit buffers: 33 bytes (FIFO)
Transmit buffers: 1 byte
Receive buffers: 40 bytes (FIFO)
Receive buffers: 1 byte
Up to 4 frames receivable
CPU processing
Processing before start of communication (data
setting)
Processing before start of communication
(data setting)
Setting, controlling each communication status
Writing data to transmit buffers
Reading data from receive buffers
Setting, controlling each communication
status
Data write processing in one-byte units
Data read processing in one-byte units
Transmission control of slave status, etc.
Multiple-frame control, repeat master-
request processing
Hard processing
Bit processing (modem, error detection)
Bit processing (modem, error detection)
Field processing (generation/control)
Field processing (generation/control)
Arbitration result detection
Arbitration result detection
Parity processing (generation/error detection)
ACK/NACK automatic response
Automatic retransmit-of-data processing
Automatic remaster processing
Parity processing (generation/error
detection)
ACK/NACK automatic response
Automatic retransmit-of-data processing
Automatic transmission processing of slave
status, etc.
Multiple-frame reception processing
Note The µPD780702Y only supports an IEBus controller that operates at fX = 6.291456 MHz.
Remark fX: System clock frequency
Preliminary Product Information U13920EJ1V0PM00
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