""" # TOP2049 Open Source programming suite # # Generic SRAM chip # # Copyright (c) 2011 Michael Buesch # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License along # with this program; if not, write to the Free Software Foundation, Inc., # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. """ from libtoprammer.chip import * class Chip_genericSRAM(Chip): def __init__(self, chipPackage, chipPinVCC, chipPinGND, VCCVoltage, nrAddressBits, nrDataBits): Chip.__init__(self, chipPackage = chipPackage, chipPinVCC = chipPinVCC, chipPinGND = chipPinGND) self.VCCVoltage = VCCVoltage self.nrAddressBits = nrAddressBits self.nrAddressBytes = int(math.ceil((float(self.nrAddressBits) - 0.1) / 8)) self.nrDataBits = nrDataBits assert(nrDataBits == 8) def erase(self): self.writeRAM(int2byte(0) * self.__sizeBytes()) def test(self): generic = GenericAlgorithms(self) generic.simpleTest(self.readRAM, self.writeRAM, self.__sizeBytes()) def readRAM(self): image = [] self.progressMeterInit("Reading SRAM", self.__sizeBytes()) self.__turnOnChip() self.__setControlPins(CE=0, OE=0, WE=1) nrBytes = 0 for addr in range(0, self.__sizeBytes()): self.progressMeter(addr) self.__setAddress(addr) self.__readData() nrBytes += 1 if nrBytes == self.top.getBufferRegSize(): image.append(self.top.cmdReadBufferReg(nrBytes)) nrBytes = 0 image.append(self.top.cmdReadBufferReg(nrBytes)) self.__setControlPins(CE=1, OE=1, WE=1) self.progressMeterFinish() return b"".join(image) def writeRAM(self, image): if len(image) > self.__sizeBytes(): self.throwError("Invalid memory image size %d (expected max %d)" %\ (len(image), self.__sizeBytes())) self.progressMeterInit("Writing SRAM", self.__sizeBytes()) self.__turnOnChip() self.__setControlPins(CE=0, OE=1, WE=1) for addr in range(0, len(image)): self.progressMeter(addr) self.__setAddress(addr) self.__writeData(image[addr]) self.__setControlPins(CE=0, OE=1, WE=0) self.top.cmdDelay(0.00000007) # Delay at least 70 nsec self.__setControlPins(CE=0, OE=1, WE=1) self.__setControlPins(CE=1, OE=1, WE=1) self.progressMeterFinish() def __sizeBytes(self): return (1 << self.nrAddressBits) def __turnOnChip(self): self.__setControlPins(CE=1, OE=1, WE=1) self.top.cmdSetVCCVoltage(self.VCCVoltage) self.applyGND(True) self.applyVCC(True) self.lastAddress = None def __setControlPins(self, CE=1, OE=1, WE=1): value = 0 if CE: value |= 1 if OE: value |= 2 if WE: value |= 4 self.top.cmdFPGAWrite(0x11, value) def __writeData(self, data): data = byte2int(data) self.top.cmdFPGAWrite(0x10, data) def __readData(self): self.top.cmdFPGARead(0x10) def __setAddress(self, addr): for i in range(0, self.nrAddressBytes): shift = 8 * i mask = 0xFF << shift if self.lastAddress is None or\ (self.lastAddress & mask) != (addr & mask): self.top.cmdFPGAWrite(0x12 + i, (addr & mask) >> shift) self.lastAddress = addr