實(shí)現(xiàn)真空熒光屏VFD的顯示

1、實(shí)現(xiàn)真空熒光屏VFD的顯示最近接到一個(gè)工作任務(wù)，就是在Windows平臺(tái)，通過(guò)寫(xiě)串口的方式，實(shí)現(xiàn)真空熒光屏VFD的顯示。VFD是通過(guò)淘寶購(gòu)來(lái)的，隨產(chǎn)品附來(lái)的只有一份顯示屏規(guī)格說(shuō)明及保修卡。如果要寫(xiě)程序?qū)崿F(xiàn)VFD顯示，需要參照產(chǎn)品指令說(shuō)明。以下是部分指令的說(shuō)明。第一步：選定需要使用的指令類(lèi)型。在我的代碼里，使用的是EPSON POS指令類(lèi)型。相應(yīng)代碼段：BOOL fState;BYTE SendBuffer256;DWORD WrittenLen;SendBuffer0 = 0x01; /Command Type: 01 - EPSON POSfState = WriteFile(m_hCom,

2、 (void*)SendBuffer, 1, &WrittenLen, NULL);第二步：發(fā)送清屏、定位及顯示字串等命令。清屏代碼段：SendBuffer0 = 0x0C; /0x0C - Clear display screen fState = WriteFile(m_hCom, (void*)SendBuffer, 1, &WrittenLen, NULL);清屏代碼段:/* 1F 24 x y : Move cursor to specified position 1x(column) ; 1y(row) */BYTE posi16=0;posi0 = 0x1F;po

3、si1 = 0x24;posi2 = 0x01;posi3 = 0x01;fState = WriteFile(m_hCom, (void*)posi, 4, &WrittenLen, NULL);顯示字串的代碼段 memset(SendBuffer, 0, sizeof(SendBuffer); if(bCashBox) sprintf(char*)SendBuffer, "Total:"); nNumberOfBytes = 6; else if(bUpdateSubTotal) if(giProductListNum = 0) sprintf(char*)Se

4、ndBuffer, ""); nNumberOfBytes = 0; else sprintf(char*)SendBuffer, "SubTotal:"); nNumberOfBytes = 9; else sprintf(char*)SendBuffer, "Total:"); nNumberOfBytes = 6; if(nNumberOfBytes != 0) fState = WriteFile(m_hCom, (void*)&SendBuffer, nNumberOfBytes, &WrittenLen,

5、NULL); if (!fState) break; 以下是完整功能函數(shù)。void CPosDemoDlgMain:UpdateSubDisp(BOOL bUpdateSubTotal, BOOL bCashBox)BOOL Result = FALSE, fState;volatile HANDLE m_hCom=NULL;/ 串口句柄COMMTIMEOUTS timeOuts;COMSTAT comState;DCB dcb; BYTE SendBuffer256, posi16=0;DWORD WrittenLen, dwErrorFlags; int len, x, nNumberOf

6、Bytes;while(1)/ Open COM port.m_hCom = CreateFile(gComPortID2,GENERIC_READ|GENERIC_WRITE,/ enable read and write0,/ 獨(dú)占方式NULL,OPEN_EXISTING,/ 打開(kāi)而不是創(chuàng)建0, /FILE_ATTRIBUTE_NORMAL|FILE_FLAG_OVERLAPPED,/ 重疊方式NULL);if (m_hCom = INVALID_HANDLE_VALUE)break;SetupComm(m_hCom, 2048, 2048);/ Set timeout.timeOuts.

7、ReadIntervalTimeout = 1000;timeOuts.ReadTotalTimeoutMultiplier = 500;timeOuts.ReadTotalTimeoutConstant = 5000;timeOuts.WriteTotalTimeoutMultiplier = 500;timeOuts.WriteTotalTimeoutConstant = 5000;if (!SetCommTimeouts(m_hCom, &timeOuts)break;/ 設(shè)置傳輸參數(shù)if (!GetCommState(m_hCom, &dcb)/ get parabre

8、ak;dcb.BaudRate = _wtol(gComBaudRate2);dcb.ByteSize = _wtoi(gComDataBit2);if (_wcsicmp(gComParity2, L"none")=0)dcb.Parity = NOPARITY;else if (_wcsicmp(gComParity2, L"odd")=0)dcb.Parity = ODDPARITY;else if (_wcsicmp(gComParity2, L"odd")=0)dcb.Parity = EVENPARITY;if (_wcs

9、icmp(gComStopBit2, L"1") =0)dcb.StopBits = ONESTOPBIT;else if (_wcsicmp(gComStopBit2, L"2") =0)dcb.StopBits = TWOSTOPBITS;if (!SetCommState(m_hCom, &dcb)/ set parabreak;PurgeComm(m_hCom, PURGE_TXCLEAR | PURGE_RXCLEAR);/ 清除發(fā)送、接收緩沖區(qū)ClearCommError(m_hCom, &dwErrorFlags, &

10、;comState);/ 清除錯(cuò)誤 SendBuffer0 = 0x01; /Command Type: 01 - EPSON POS fState = WriteFile(m_hCom, (void*)SendBuffer, 1, &WrittenLen, NULL);if (!fState)break; SendBuffer0 = 0x0C; /0x0C - Clear display screen fState = WriteFile(m_hCom, (void*)SendBuffer, 1, &WrittenLen, NULL);if (!fState)break; /

11、* 1F 24 x y : Move cursor to specified position 1x(column) 20 ; 1y(row) 2 */ posi0 = 0x1F; posi1 = 0x24; posi2 = 0x01; posi3 = 0x01; fState = WriteFile(m_hCom, (void*)posi, 4, &WrittenLen, NULL);if (!fState)break; memset(SendBuffer, 0, sizeof(SendBuffer); if(bCashBox) sprintf(char*)SendBuffer, &

12、quot;Total:"); nNumberOfBytes = 6; else if(bUpdateSubTotal) if(giProductListNum = 0) sprintf(char*)SendBuffer, ""); nNumberOfBytes = 0; else sprintf(char*)SendBuffer, "SubTotal:"); nNumberOfBytes = 9; else sprintf(char*)SendBuffer, "Total:"); nNumberOfBytes = 6; if

13、(nNumberOfBytes != 0) fState = WriteFile(m_hCom, (void*)&SendBuffer, nNumberOfBytes, &WrittenLen, NULL); if (!fState) break; memset(SendBuffer, 0, sizeof(SendBuffer); if(bCashBox) sprintf(char*)SendBuffer, "%d.%02d", gTotalPrice/100, gTotalPrice%100); else if(bUpdateSubTotal) if(gi

14、ProductListNum = 0) strcpy(char*)SendBuffer, ""); else strcpy(char*)SendBuffer, m_sSubTotalBuf); else sprintf(char*)SendBuffer, "%d.%02d", gTotalPrice/100, gTotalPrice%100); len = strlen(char*)SendBuffer); x = 20 - len; /set display position posi0 = 0x1F; posi1 = 0x24; posi2 = to

15、Hex(x); posi3 = 0x01; fState = WriteFile(m_hCom, (void*)posi, 4, &WrittenLen, NULL);if (!fState)break; /display cashfState = WriteFile(m_hCom, (void*)&SendBuffer, len, &WrittenLen, NULL);if (!fState)break; /= row 2 = /set display position (row 2) posi0 = 0x1F; posi1 = 0x24; posi2 = 0x01;

16、 posi3 = 0x02; fState = WriteFile(m_hCom, (void*)posi, 4, &WrittenLen, NULL);if (!fState)break; memset(SendBuffer, 0, sizeof(SendBuffer); if(bCashBox) sprintf(char*)SendBuffer, "Cash Change:"); fState = WriteFile(m_hCom, (void*)&SendBuffer, 12, &WrittenLen, NULL); else if(bUpda

17、teSubTotal) sprintf(char*)SendBuffer, "Total:"); fState = WriteFile(m_hCom, (void*)&SendBuffer, 6, &WrittenLen, NULL); else sprintf(char*)SendBuffer, "Payment:"); fState = WriteFile(m_hCom, (void*)&SendBuffer, 8, &WrittenLen, NULL); if (!fState)break; memset(SendB

18、uffer, 0, sizeof(SendBuffer); if(bCashBox) if (m_Payment < gTotalPrice) sprintf(char*)SendBuffer, "-%d.%02d", (gTotalPrice - m_Payment)/100, (gTotalPrice - m_Payment)%100); else sprintf(char*)SendBuffer, "%d.%02d", (m_Payment - gTotalPrice)/100, (m_Payment - gTotalPrice)%100); else if(bUpdateSubTotal) sprintf(char*)SendBuffer, "%d.%02d", gTotalPrice/100, gTo