Serial Status Register Mn (Ssrmn) - Renesas RL78/G1P Hardware User Manual

RL78/G1P

11.3.7 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), F0102H, F0103H (SSR01)
Symbol 15 14
SSRmn 0 0
TSF
mn
0 Communication is stopped or suspended.
1 Communication is in progress.
<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.
BFF
mn
0 Valid data is not stored in the SDRmn register.
1 Valid data is stored in the SDRmn register.
<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 register only.
Caution If data is written to the SDRmn register when BFFmn = 1, the transmit/receive data stored in the
register is discarded and an overrun error (OVEmn = 1) is detected.
Remark m: Unit number (m = 0), n: Channel number (n = 0, 1)
R01UH0895EJ0100 Rev.1.00
Nov 29, 2019
Figure 11-9. Format of Serial Status Register mn (SSRmn) (1/2)
13 12 11 10
0 0 0 0
Communication status indication flag of channel n
Buffer register status indication flag of channel n
CHAPTER 11 SERIAL ARRAY UNIT
After reset: 0000H R
9 8 7 6
0 0 0 TSF BFF
mn mn
5 4 3 2
0 0 FEFm PEF
Note
n
1 0
OVF
mn mn
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