//=====================================================================
//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:on 0:off "USEDMARX"=dword:0 ; 1:on 0: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:on 0:off "USEDMARX"=dword:1 ; 1:on 0: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:on 0:off "USEDMARX"=dword:1 ; 1:on 0: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:on 0:off "USEDMARX"=dword:0 ; 1:on 0: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:on 0:off "USEDMARX"=dword:0 ; 1:on 0: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 |