参数资料
型号: XR16V798IQ-0B-EVB
厂商: Exar Corporation
文件页数: 30/56页
文件大小: 0K
描述: EVAL BOARD FOR XR16V798-B 100QFP
设计资源: XR17V798/794 Eval Board Schematic
标准包装: 1
系列: *
XR16V798
36
HIGH PERFORMANCE 2.25V TO 3.6V OCTAL UART WITH FRACTIONAL BAUD RATE
REV. 1.0.1
4.7
Modem Control Register (MCR) - Read/Write
The MCR register is used for controlling the modem interface signals or general purpose inputs/outputs.
MCR[7]: Clock Prescaler Select
Logic 0 = Divide by one. The input clock from the crystal or external clock is fed directly to the Programmable
Baud Rate Generator without further modification, i.e., divide by one (default).
Logic 1 = Divide by four. The prescaler divides the input clock from the crystal or external clock by four and
feeds it to the Programmable Baud Rate Generator, hence, data rates become one forth.
MCR[6]: Infrared Encoder/Decoder Enable
The state of this bit depends on the sampled logic level of pin ENIR during power up, following a hardware
reset (rising edge of RST# input). Afterward user can override this bit for desired operation.
Logic 0 = Enable the standard modem receive and transmit character interface.
Logic 1 = Enable infrared IrDA receive and transmit inputs/outputs. While in this mode, the TX/RX output/
input are routed to the infrared encoder/decoder. The data input and output levels will conform to the IrDA
infrared interface requirement. As such, while in this mode the infrared TX output will be a logic 0 during idle
data conditions. FCTR bit-4 may be selected to invert the RX input signal level going to the decoder for
infrared modules that provide rather an inverted output.
MCR[5]: Xon-Any Enable
Logic 0 = Disable Xon-Any function (default).
Logic 1 = Enable Xon-Any function. In this mode any RX character received will enable Xon, resume data
transmission.
MCR[4]: Internal Loopback Enable
Logic 0 = Disable loopback mode (default).
Logic 1 = Enable local loopback mode, see loopback section and Figure 11.
MCR[3]: Send Char Immediate (OP2 in Local Loopback Mode)
This bit is used to transmit a character immediately irrespective of the bytes currently in the transmit FIFO. The
data byte must be loaded into the transmit holding register (THR) immediately following the write to this bit (to
set it to a ’1’). In other words, no other register must be accessed between setting this bit and writing to the
THR. The loaded byte will be transmitted ahead of all the bytes in the TX FIFO, immediately after the character
currently being shifted out of the transmit shift register is sent out. The existing line parameters (parity, stop
bits) will be used when composing the character. This bit is self clearing, therefore, must be set before sending
a custom characer each time. Please note that the Transmitter must be enabled for this function (MSR[3] = 0).
Also, if software flow control is enabled, the software flow control characters (Xon, Xoff) have higher priority
and will get shifted out before the custom byte is transmitted.
Logic 0 = Send Char Immediate disabled (default).
Logic 1 = Send Char Immediate enabled.
In Local Loopback Mode (MCR[4] = 1), this bit acts as the legacy OP2 output and controls the CD bit in the
MSR register as shown in Figure 11. Please make sure that this bit is a ’0’ when exiting the Local Loopback
Mode.
MCR[2]: DTR# or RTS# for Auto Flow Control (OP1 in Local Loopback Mode)
DTR# or RTS# auto hardware flow control select. This bit is in effect only when auto RTS/DTR is enabled by
EFR bit-6. DTR# selection is associated with DSR# and RTS# is with CTS#.
Logic 0 = Uses RTS# and CTS# pins for auto hardware flow control.
Logic 1 = Uses DTR# and DSR# pins for auto hardware flow control.
In Local Loopback mode (MCR[4] = 1), this bit acts as the legacy OP1 output and controls the RI bit in the MSR
register, as shown in Figure 11.
相关PDF资料
PDF描述
XR16V798IQ-0A-EVB EVAL BOARD FOR XR16V798-A 100QFP
XR16V698IQ-0B-EVB EVAL BOARD FOR XR16V698-B 100QFP
XR16V698IQ-0A-EVB EVAL BOARD FOR XR16V698-A 100QFP
KIT33972AEWEVBE KIT EVALUATION FOR MC33972
EBM31DCMS CONN EDGECARD 62POS .156 WW
相关代理商/技术参数
参数描述
XR16V798IQ-F 功能描述:UART 接口集成电路 UART RoHS:否 制造商:Texas Instruments 通道数量:2 数据速率:3 Mbps 电源电压-最大:3.6 V 电源电压-最小:2.7 V 电源电流:20 mA 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:LQFP-48 封装:Reel
XR16V798IQTR-F 制造商:Exar Corporation 功能描述:UART 8-CH 64Byte FIFO 2.5V/3.3V 100-Pin PQFP T/R
XR-1790 制造商:未知厂家 制造商全称:未知厂家 功能描述:Audio Schematic
XR17C152 制造商:EXAR 制造商全称:EXAR 功能描述:5V PCI BUS DUAL UART
XR17C152CM 制造商:EXAR 制造商全称:EXAR 功能描述:5V PCI BUS DUAL UART