REV. 4.4.1 4.3.1 IER versus Receive FIFO Interrupt Mode Operation When the receive FIFO (FCR" />
參數(shù)資料
型號: ST16C2550CJ-0A-EB
廠商: Exar Corporation
文件頁數(shù): 10/37頁
文件大?。?/td> 0K
描述: EVAL BOARD FOR ST16C2550 44PLCC
標準包裝: 1
系列: *
ST16C2550
18
2.97V TO 5.5V DUART WITH 16-BYTE FIFO
REV. 4.4.1
4.3.1
IER versus Receive FIFO Interrupt Mode Operation
When the receive FIFO (FCR BIT-0 = 1) and receive interrupts (IER BIT-0 = 1) are enabled, the RHR interrupts
(see ISR bits 2 and 3) status will reflect the following:
A. The receive data available interrupts are issued to the host when the FIFO has reached the programmed
trigger level. It will be cleared when the FIFO drops below the programmed trigger level.
B. FIFO level will be reflected in the ISR register when the FIFO trigger level is reached. Both the ISR register
status bit and the interrupt will be cleared when the FIFO drops below the trigger level.
C. The receive data ready bit (LSR BIT-0) is set as soon as a character is transferred from the shift register to
the receive FIFO. It is reset when the FIFO is empty.
4.3.2
IER versus Receive/Transmit FIFO Polled Mode Operation
When FCR BIT-0 equals a logic 1 for FIFO enable; resetting IER bits 0-3 enables the ST16C2550 in the FIFO
polled mode of operation. Since the receiver and transmitter have separate bits in the LSR either or both can
be used in the polled mode by selecting respective transmit or receive control bit(s).
A. LSR BIT-0 indicates there is data in RHR or RX FIFO.
B. LSR BIT-1 indicates an overrun error has occurred and that data in the FIFO may not be valid.
C. LSR BIT 2-4 provides the type of receive data errors encountered for the data byte in RHR, if any.
D. LSR BIT-5 indicates Transmit FIFO is empty.
E. LSR BIT-6 indicates when both the transmit FIFO and TSR are empty.
F. LSR BIT-7 indicates a data error in at least one character in the RX FIFO.
IER[0]: RHR Interrupt Enable
The receive data ready interrupt will be issued when RHR has a data character in the non-FIFO mode or when
the receive FIFO has reached the programmed trigger level in the FIFO mode.
Logic 0 = Disable the receive data ready interrupt (default).
Logic 1 = Enable the receiver data ready interrupt.
IER[1]: THR Interrupt Enable
This bit enables the Transmit Ready interrupt which is issued whenever the Transmit FIFO becomes empty. If
the Transmit FIFO is empty when this bit is enabled, an interrupt will be generated.
Logic 0 = Disable Transmit Ready interrupt (default).
Logic 1 = Enable Transmit Ready interrupt.
IER[2]: Receive Line Status Interrupt Enable
If any of the LSR register bits 1, 2, 3 or 4 is a logic 1, it will generate an interrupt to inform the host controller
about the error status of the current data byte in FIFO. LSR bit-1 generates an interrupt immediately when the
character has been received. LSR bits 2-4 generate an interrupt when the character with errors is read out of
the FIFO.
Logic 0 = Disable the receiver line status interrupt (default).
Logic 1 = Enable the receiver line status interrupt.
IER[3]: Modem Status Interrupt Enable
Logic 0 = Disable the modem status register interrupt (default).
Logic 1 = Enable the modem status register interrupt.
IER[7:4]: Reserved
相關PDF資料
PDF描述
MFP 1/8"CR48"BX HTSHRNK MFP 1/8"X4'(8')CLR
UPA1E122MHD1TO CAP ALUM 1200UF 25V 20% RADIAL
VE-20T-EX CONVERTER MOD DC/DC 6.5V 75W
RP60-4812SG-HC CONV DC/DC 60W 36-75VIN 12VOUT
ESM10DRTH-S13 CONN EDGECARD 20POS .156 EXTEND
相關代理商/技術參數(shù)
參數(shù)描述
ST16C2550CJ44 制造商:EXAR 制造商全稱:EXAR 功能描述:2.97V TO 5.5V DUART WITH 16-BYTE FIFO
ST16C2550CJ44-F 功能描述:UART 接口集成電路 2.97V-5.5V 16B FIFO temp 0C to 70C; UART RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 數(shù)據(jù)速率:3 Mbps 電源電壓-最大:3.6 V 電源電壓-最小:2.7 V 電源電流:20 mA 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:LQFP-48 封裝:Reel
ST16C2550CJ44TR-F 功能描述:UART 接口集成電路 DUAL UART W/16BYTE FIFO RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 數(shù)據(jù)速率:3 Mbps 電源電壓-最大:3.6 V 電源電壓-最小:2.7 V 電源電流:20 mA 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:LQFP-48 封裝:Reel
ST16C2550CP40 功能描述:UART 接口集成電路 DUAL UART W/16 BYTE FIFO RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 數(shù)據(jù)速率:3 Mbps 電源電壓-最大:3.6 V 電源電壓-最小:2.7 V 電源電流:20 mA 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:LQFP-48 封裝:Reel
ST16C2550CP40-F 功能描述:UART 接口集成電路 DUAL UART W/16 BYTE FIFO RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 數(shù)據(jù)速率:3 Mbps 電源電壓-最大:3.6 V 電源電壓-最小:2.7 V 電源電流:20 mA 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:LQFP-48 封裝:Reel