Renesas RL78 Series User Manual page 407

RL78/G1D
13.3.7 Serial status register mn (SSRmn)
The SSRmn register is a register that indicates the communication status and error occurrence status of channel n. The
errors indicated by this register are a framing error, parity error, and overrun error.
The SSRmn register can be read by a 16-bit memory manipulation instruction.
The lower 8 bits of the SSRmn register can be set with an 8-bit memory manipulation instruction with SSRmnL.
Reset signal generation clears the SSRmn register to 0000H.
Address: F0100H, F0101H (SSR00) to F0106H, F0107H (SSR03),
F0140H, F0141H (SSR10), F0142H, F0143H (SSR11)
Symbol 15 14
SSRmn 0 0
TSFmn
0
1
<Clear conditions>
● The STmn bit of the STm register is set to 1 (communication is stopped) or the SSmn bit of the SSm register is
set to 1 (communication is suspended).
● Communication ends.
<Set condition>
● Communication starts.
BFFmn
0
1
<Clear conditions>
● Transferring transmit data from the SDRmn register to the shift register ends during transmission.
● Reading receive data from the SDRmn register ends during reception.
● The STmn bit of the STm register is set to 1 (communication is stopped) or the SSmn bit of the SSm register is
set to 1 (communication is enabled).
<Set conditions>
● Transmit data is written to the SDRmn register while the TXEmn bit of the SCRmn register is set to 1
(transmission or transmission and reception mode in each communication mode).
● Receive data is stored in the SDRmn register while the RXEmn bit of the SCRmn register is set to 1 (reception or
transmission and reception mode in each communication mode).
● A reception error occurs.
Note The SSR01 and SSR03 registers only.
Caution When the CSI is performing reception operations in the SNOOZE mode (SWCm = 1), the BFFmn
flag will not change.
Remark m: Unit number (m = 0, 1), n: Channel number (n = 0 to 3 for m = 0, n = 0, 1 for m = 1)
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
Figure 13-11. Format of Serial Status Register mn (SSRmn) (1/2)
13 12 11 10
0 0 0 0
Communication status indication flag of channel n
Communication is stopped or suspended.
Communication is in progress.
Buffer register status indication flag of channel n
Valid data is not stored in the SDRmn register.
Valid data is stored in the SDRmn register.
CHAPTER 13 SERIAL ARRAY UNIT
After reset: 0000H
9 8 7 6
0 0 0 TSF BFF
mn mn
R
5 4 3 2
0 0 FEFm PEF
Note
n
1 0
OVF
mn mn
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