UPD78F0411GA-GAM-AX Datasheet, PDF (433/564 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 16 MANCHESTER CODE GENERATOR
(2) Transmit operation
In bit sequential buffer mode, data is transmitted in 1- to 8-bit units. Transmission is enabled if bit 7 (MC0PWR)
of MCG control register 0 (MC0CTL0) is set to 1.
The output value while transmission is suspended can be set by using bit 0 (MC0OLV) of the MC0CTL0 register.
A transmission starts by writing a value to the MCG transmit buffer register (MC0TX) after setting the transmit
data bit length to the MCG transmit bit count specification register (MC0BIT). At the transmission start timing, the
MC0BIT value is transferred to the 3-bit counter and data of MC0TX is transferred to the 8-bit shift register. An
interrupt request signal (INTMCG) occurs at the timing that the MC0TX value is transferred to the 8-bit shift
register. The 8-bit shift register is continuously shifted by the baud rate clock and is output from the MCGO pin.
When continuous transmission is executed, the next data is set to MC0BIT and MC0TX during data transmission
after INTMCG occurs.
To transmit continuously, writing the next transfer data to MC0TX must be complete within the period (3) and (4)
in Figure 16-9. Rewrite MC0BIT before writing to MC0TX during continuous transmission.
Figure 16-9. Timing of Bit Sequential Buffer Mode (LSB First) (1/4)
(1) Transmit timing (MC0OLV = 1, total transmit bit length = 8 bits)
MC0PWR
MC0OLV
MC0OSL
MC0BIT
3-bit counter
MC0TX
8-bit shift register
Baud rate clock
“111”
“111” “110” “101” “100” “011” “010” “001”
“000”
“10010110” (8-bit data)
“10010110” “x1001011” “xx100101” “xxx10010” “xxxx1001” “xxxxx100” “xxxxxx10”
“xxxxxxx1”
MCGO pin
MC0TSF
INTMCG
User’s Manual U18698EJ1V0UD
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