ML63611 User’s Manual
Chapter 12 Serial Port (SIO)
12 – 11
OPTION B (D): 1.5 V (3.0 V), With regulator
circuit for LCD bias
OPTION A (C): 1.5 V (3.0 V), Without regulator
circuit for LCD bias
(8) Serial port status register (SSTAT)
SSTAT is a 4-bit special function register (SFR) used to indicate the status of serial port send/receive.
SSTAT is initialized to “0” at system reset.
SSTAT is a read-only register, and the content is reset every time it is read.
bit 3: BFULL (send Buffer FULL flag)
This bit is enabled in both UART and synchronous modes, and is set to “1” when send data is set
to STBUFL/H in the send mode, and reset to “0” when the send data is transferred to the send
register.
When BFULL is set to “1” and send data is set (written) to STBUFL/H, the previous data set to
those registers is overwritten and lost. Always set data only after verifying that the BFULL flag
is “0”.
bit 2: PERR (Parity ERRor flag)
This bit is enabled in both UART and synchronous modes, and is set to “1” when the parity for
the received data does not match the parity bit attached to the data.
bit 1: OERR (Overrun ERRor flag)
This bit is enabled in both UART and synchronous modes, and is set to “1” when data reception is
completed and the data received the previous time has still not been transferred to the CPU. In this
case, the new data cannot be transferred to SRBUFL/H.
bit 0: FERR (Framing ERRor flag)
This is only enabled in the UART mode and is set to “1” in the following instances.
(1) when a “1” is detected in start bit sampling
(2) when a “0” is detected in stop bit sampling
In either case a receive interrupt request signal (SRINT) is generated.
BFULL
PERR
OERR
FERR
Send buffer status flag
0 : Send buffer empty (initial value)
1 : Send buffer full
Parity error flag
0 : No parity error (initial value)
1 : Parity error
Overrun flag
0 : No overrun error (initial value)
1 : Overrun error
Framing error
0 : No framing error (initial value)
1 : Framing error
SSTAT (0ADH)
(R)
bit 3
bit 2
bit 1
bit 0
Содержание ML63611
Страница 9: ...Chapter 1 Overview...
Страница 33: ...Chapter 2 CPU and Memory Spaces...
Страница 42: ...Chapter 3 CPU Control Functions...
Страница 49: ...Chapter 4 Interrupt INT...
Страница 62: ...Chapter 5 Clock Generator Circuit OSC...
Страница 71: ...Chapter 6 Time Base Counter TBC...
Страница 75: ...Chapter 7 Timers TIMER...
Страница 99: ...Chapter 8 100 Hz Timer Counter 100HzTC...
Страница 103: ...Chapter 9 Watchdog Timer WDT...
Страница 108: ...Chapter 10 Ports INPUT I O PORT...
Страница 140: ...Chapter 11 Melody Driver MELODY...
Страница 152: ...Chapter 12 Serial Port SIO...
Страница 179: ...Chapter 13 LCD Driver LCD...
Страница 200: ...Chapter 14 Battery Low Detect Circuit BLD...
Страница 204: ...Chapter 15 Power Supply Circuit POWER...
Страница 215: ...Chapter 16 A D Converter ADC...
Страница 238: ...Appendixes...
Страница 271: ...ML63611 User s Manual First Edition May 2001 Second Edition June 2001 2001 Oki Electric Industry Co Ltd PEUL63611 02...