TCC89x串口设置要点
//=====================================================================
本文引用地址:https://www.eepw.com.cn/article/201609/304828.htm//TITLE:
// TCC89x串口设置要点
//AUTHOR:
// norains
//DATE:
// Thursday 29-March-2011
//Environment:
// Visual Studio 2005
// Windows CE 6.0
// Telechips TCC8900
//=====================================================================
对于Telechips的TCC89x系列来说,串口资源不可谓不丰富,整整六组串口,应该能满足大多数的应用场合了。
如果运行的是Windows CE操作系统的话,除去作为调试的Debug口,那么还剩下五组可供应用程序使用。而这五组串口的使能,并不需要做太多的工作,只需要书写相应的注册表数值即可。只不过比较可惜的的是,Telechips原版的注册表,只使能COM1~COM3这三组,而COM4和COM5只能自己动手。不过这对于经验丰富的开发者来说,并不是一件很难的事情,完全可以依样画瓢。只不过,有下面几点需要注意。
1. COM_ChNum和COM_PortNum必须对应
COM_ChNum是串口的通道,COM_PortNum是对应的PIN脚,这两个数值都可以在注册表中进行设置。但这并不意味着,可以随意设置,而必须要按照如下的映射关系:
COM_ChNum | COM_PortNum |
1 | 1 |
2 | 4 |
3 | 5 |
4 | 2 |
5 | 3 |
简单点来说,如果COM_ChNum为3的话,那么COM_PortNum就必须为5。为什么会有如此奇怪的关系呢?其实这是因为代码中规定的。打开Magellan/Src/LIB/SOC/UART/TCC89x/tca_serial.c文件,查看tca_serial_portinit函数,就可以发现代码中已经一一映射,如下图所示:

而注册表必须要和代码保持一致,所以COM_ChNum和COM_PortNum的关系也就定死了。
2. DMA不支持Channel4~Channel5
这个要点在Datasheet的800页有如下的说明:

翻译为中文,大致是:DMA发送和接收在UART的Channel0~3是可用的。但如果是Channel4和Channel5,因为无法使用硬件控制,所以无法DMA。如果一定要使用DMA传输方式,请确保使用的是Channel0~3。
因为在Telechips的默认注册表中,Channel0~3已经被调试口和COM1~COM3所使用了,剩下的COM4和COM5只能放弃DMA的方式。而具体到注册表,则是USEDMATX和USEDMARX这两个键值的数值必须为0。
最后,则是看看完整的串口设置信息列表,Telechips没有给出的COM4和COM5设置也一并在表格中列出:
序号 | Channel | Port | Tx | Rx | 注册表 | DMA |
Debug | 0 | 0 | GPIO E[0] | GPIO E[1] | 无 | 支持 |
COM1 | 3 | 5 | GPIO D[17] | GPIO D[18] | [HKEY_LOCAL_MACHINE/Drivers/BuiltIn/Serial1] DeviceArrayIndex=dword:0 COM_ChNum=dword:3 COM_PortNum=dword:5 MemBase=dword:B100C000 irq=dword:2F MemLen=dword:2C InterruptBitsShift=dword:0 ; UART 0 Interrupt Sub Register shift bit. ISTTimeouts=dword:200; every 512 ticks checking Modem status. Prefix=COM Index=dword:1 Dll=tcc_serial.dll Order=dword:1 Priority256=dword:e0 Port=COM1: DeviceType=dword:0 FriendlyName=Serial Cable on COM1: Tsp=unimodem.dll IsrDll=tcc_giisr.dll IsrHandler=ISRHandler DMAIsrHandler=DMAUARTISRHandler USEDMATX=dword:1; 1:on0:off USEDMARX=dword:0; 1:on0:off IClass={CC5195AC-BA49-48a0-BE17-DF6D1B0173DD} DevConfig=hex: 10,00, 00,00, 05,00,00,00, 10,01,00,00, 00,4B,00,00, 00,00, 08, 00, 00, 00,00,00,00 | 支持 |
COM2 | 1 | 1 | GPIO E[4] | GPIO E[5] | [HKEY_LOCAL_MACHINE/Drivers/BuiltIn/Serial2] DeviceArrayIndex=dword:1 COM_ChNum=dword:1 COM_PortNum=dword:1 MemBase=dword:B1008000 irq=dword:2F MemLen=dword:2C InterruptBitsShift=dword:0 ; UART Interrupt Sub Register shift bit. ISTTimeouts=dword:200; every 512 ticks checking Modem status. Prefix=COM Index=dword:2 Dll=tcc_serial.dll Order=dword:1 Priority256=dword:e0 Port=COM2: DeviceType=dword:0 FriendlyName=Serial Cable on COM2: Tsp=unimodem.dll IsrDll=tcc_giisr.dll IsrHandler=ISRHandler DMAIsrHandler=DMAUARTISRHandler USEDMATX=dword:1; 1:on0:off USEDMARX=dword:1; 1:on0:off IClass={CC5195AC-BA49-48a0-BE17-DF6D1B0173DD} DevConfig=hex: 10,00, 00,00, 05,00,00,00, 10,01,00,00, 00,4B,00,00, 00,00, 08, 00, 00, 00,00,00,00 | 支持 |
COM3 | 2 | 4 | GPIO D[13] | GPIO D[14] | [HKEY_LOCAL_MACHINE/Drivers/BuiltIn/Serial3] DeviceArrayIndex=dword:2 COM_ChNum=dword:2 COM_PortNum=dword:4 MemBase=dword:B1004000 irq=dword:2F MemLen=dword:2C InterruptBitsShift=dword:0 ; UART Interrupt Sub Register shift bit. ISTTimeouts=dword:200; every 512 ticks checking Modem status. Prefix=COM Index=dword:3 Dll=tcc_serial.dll Order=dword:1 Priority256=dword:e0 Port=COM3: DeviceType=dword:0 FriendlyName=Serial Cable on COM3: Tsp=unimodem.dll IsrDll=tcc_giisr.dll IsrHandler=ISRHandler DMAIsrHandler=DMAUARTISRHandler USEDMATX=dword:1; 1:on0:off USEDMARX=dword:1; 1:on0:off IClass={CC5195AC-BA49-48a0-BE17-DF6D1B0173DD} DevConfig=hex: 10,00, 00,00, 05,00,00,00, 10,01,00,00, 00,4B,00,00, 00,00, 08, 00, 00, 00,00,00,00 | 支持 |
COM4 | 4 | 2 | GPIO E[8] | GPIO E[9] | [HKEY_LOCAL_MACHINE/Drivers/BuiltIn/Serial4] DeviceArrayIndex=dword:3 COM_ChNum=dword:4 COM_PortNum=dword:2 MemBase=dword:B1000000 irq=dword:2F MemLen=dword:2C InterruptBitsShift=dword:0 ; UART Interrupt Sub Register shift bit. ISTTimeouts=dword:200; every 512 ticks checking Modem status. Prefix=COM Index=dword:4 Dll=tcc_serial.dll Order=dword:1 Priority256=dword:e0 Port=COM4: DeviceType=dword:0 FriendlyName=Serial Cable on COM4: Tsp=unimodem.dll IsrDll=tcc_giisr.dll IsrHandler=ISRHandler DMAIsrHandler=DMAUARTISRHandler USEDMATX=dword:0; 1:on0:off USEDMARX=dword:0; 1:on0:off IClass={CC5195AC-BA49-48a0-BE17-DF6D1B0173DD} DevConfig=hex: 10,00, 00,00, 05,00,00,00, 10,01,00,00, 00,4B,00,00, 00,00, 08, 00, 00, 00,00,00,00 | 不支持 |
COM5 | 5 | 3 | GPIO E[10] | GPIO E[11] | [HKEY_LOCAL_MACHINE/Drivers/BuiltIn/Serial5] DeviceArrayIndex=dword:4 COM_ChNum=dword:5 COM_PortNum=dword:3 MemBase=dword:B0FFC000 irq=dword:2F MemLen=dword:2C InterruptBitsShift=dword:0 ; UART Interrupt Sub Register shift bit. ISTTimeouts=dword:200; every 512 ticks checking Modem status. Prefix=COM Index=dword:5 Dll=tcc_serial.dll Order=dword:1 Priority256=dword:e0 Port=COM5: DeviceType=dword:0 FriendlyName=Serial Cable on COM5: Tsp=unimodem.dll IsrDll=tcc_giisr.dll IsrHandler=ISRHandler DMAIsrHandler=DMAUARTISRHandler USEDMATX=dword:0; 1:on0:off USEDMARX=dword:0; 1:on0:off IClass={CC5195AC-BA49-48a0-BE17-DF6D1B0173DD} DevConfig=hex: 10,00, 00,00, 05,00,00,00, 10,01,00,00, 00,4B,00,00, 00,00, 08, 00, 00, 00,00,00,00 | 不支持 |
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