//=====================================================================
//TITLE:
// TCC89x串口設置要點
//AUTHOR:
// norains
//DATE:
// Thursday 29-March-2011
//Environment:
// Visual Studio 2005
// Windows CE 6.0
// Telechips TCC8900
//=====================================================================
對于Telechips的TCC89x系列來說，串口資源不可謂不豐富，整整六組串口，應該能滿足大多數(shù)的應用場合了。
如果運行的是Windows CE操作系統(tǒng)的話，除去作為調(diào)試的Debug口，那么還剩下五組可供應用程序使用。而這五組串口的使能，并不需要做太多的工作，只需要書寫相應的注冊表數(shù)值即可。只不過比較可惜的的是，Telechips原版的注冊表，只使能COM1~COM3這三組，而COM4和COM5只能自己動手。不過這對于經(jīng)驗豐富的開發(fā)者來說，并不是一件很難的事情，完全可以依樣畫瓢。只不過，有下面幾點需要注意。
1. COM_ChNum和COM_PortNum必須對應
COM_ChNum是串口的通道，COM_PortNum是對應的PIN腳，這兩個數(shù)值都可以在注冊表中進行設置。但這并不意味著，可以隨意設置，而必須要按照如下的映射關系：
|
COM_ChNum |
COM_PortNum |
|
1 |
1 |
|
2 |
4 |
|
3 |
5 |
|
4 |
2 |
|
5 |
3 |
簡單點來說，如果COM_ChNum為3的話，那么COM_PortNum就必須為5。為什么會有如此奇怪的關系呢?其實這是因為代碼中規(guī)定的。打開Magellan/Src/LIB/SOC/UART/TCC89x/tca_serial.c文件，查看tca_serial_portinit函數(shù)，就可以發(fā)現(xiàn)代碼中已經(jīng)一一映射，如下圖所示：
而注冊表必須要和代碼保持一致，所以COM_ChNum和COM_PortNum的關系也就定死了。
2. DMA不支持Channel4~Channel5
這個要點在Datasheet的800頁有如下的說明：
翻譯為中文，大致是：DMA發(fā)送和接收在UART的Channel0~3是可用的。但如果是Channel4和Channel5，因為無法使用硬件控制，所以無法DMA。如果一定要使用DMA傳輸方式，請確保使用的是Channel0~3。
因為在Telechips的默認注冊表中，Channel0~3已經(jīng)被調(diào)試口和COM1~COM3所使用了，剩下的COM4和COM5只能放棄DMA的方式。而具體到注冊表，則是"USEDMATX"和"USEDMARX"這兩個鍵值的數(shù)值必須為0。
最后，則是看看完整的串口設置信息列表，Telechips沒有給出的COM4和COM5設置也一并在表格中列出：
|
序號 |
Channel |
Port |
Tx |
Rx |
注冊表 |
DMA |
|
Debug |
0 |
0 |
GPIO E[0] |
GPIO E[1] |
無 |
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 |
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