PD72042B_15 Datasheet, PDF (40/92 Pages) Renesas Technology Corp – LSI DEVICE FOR Inter Equipment BusTM (IEBusTM) PROTOCOL CONTROL

µPD72042B
TBF
Transmission buffer
Address : 1110B (EH)
Read/write : Write
When reset : Empty
TBF is a 33-byte FIFO buffer used to hold the number of bytes of transmission data and transmission data for master
transmission and slave data transmission.
TBF can be written from the microcomputer when the TFL flag of the STR register is set to 0 (indicating that TBF
is not full).
In master transmission and slave data transmission, the following format is used to load data into TBF from the
microcomputer.
Byte 1
Byte 2
Byte 3
TBF
Number of bytes of transmission data
First byte of transmission data
Second byte of transmission data
Byte 33
[Byte 1]: Number of bytes of transmission data
Between 1 and 256 bytes can be set.
Number of bytes of
transmission data
1
2
Data set in byte 1 of TBF
01H
02H
255
FFH
256
00H
[Bytes 2 and up]: Transmission data
As much transmission data as is set in byte 1 is set in byte 2 and subsequent bytes.
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Data Sheet S13990EJ3V0DS