257 lines
8.6 KiB
C++
257 lines
8.6 KiB
C++
|
#include <stdio.h>
|
||
|
|
#include <bcm2835.h>
|
||
|
|
#include <signal.h>
|
||
|
|
#include <array>
|
||
|
|
#include <fstream>
|
||
|
|
#include <iostream>
|
||
|
|
#include <stdexcept>
|
||
|
|
#include <gz-util/string/conversion.hpp>
|
||
|
|
#include <cassert>
|
||
|
|
#include <stop_token>
|
||
|
|
#include <thread>
|
||
|
|
|
||
|
|
#include "6502_opcodes.hpp"
|
||
|
|
|
||
|
|
/* ADDRESS SETUP TIME
|
||
|
|
* depends on clock frequency, see datasheet. max 150@2MHz
|
||
|
|
* address is set after setup time (tADS) and is being hold for address hold time (tAH)
|
||
|
|
*
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
constexpr uint64_t addressSetupTimeUS = 1; // 300e-9 s
|
||
|
|
|
||
|
|
constexpr std::array<uint8_t, 15> addressPins {
|
||
|
|
27, 22, 10, 9, 11, 5, 6, 13, // A0-A7
|
||
|
|
4, 2, 18, 3, // A8-A11
|
||
|
|
23, 17, 15 // A12-A14
|
||
|
|
};
|
||
|
|
|
||
|
|
constexpr std::array<uint8_t, 8> dataPins { 24, 25, 8, 7, 12, 16, 20, 21 };
|
||
|
|
constexpr uint8_t RWb = 19; // Read/Write
|
||
|
|
constexpr uint8_t CEb = 14; // Chip Enable
|
||
|
|
constexpr uint8_t PHI2 = 26; // clock
|
||
|
|
constexpr std::array<uint8_t, 3> controlPins { CEb, RWb, PHI2 };
|
||
|
|
|
||
|
|
template<size_t N>
|
||
|
|
constexpr uint32_t getMask(const std::array<uint8_t, N>& pins) {
|
||
|
|
uint32_t mask = 0;
|
||
|
|
for (int i = 0; i < pins.size(); i++) {
|
||
|
|
/* const uint8_t bit = pins.at(i) - 1; */
|
||
|
|
mask |= (1 << pins.at(i));
|
||
|
|
}
|
||
|
|
return mask;
|
||
|
|
}
|
||
|
|
constexpr uint32_t ioMask = getMask(dataPins);
|
||
|
|
constexpr uint32_t addressMask = getMask(addressPins);
|
||
|
|
|
||
|
|
struct CurrentState {
|
||
|
|
uint16_t addressBus = 0;
|
||
|
|
uint8_t dataBus = 0;
|
||
|
|
bool RWb = true;
|
||
|
|
std::string toString() const {
|
||
|
|
std::string s;
|
||
|
|
if (RWb) {
|
||
|
|
s = "R-";
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
s = "W-";
|
||
|
|
}
|
||
|
|
s += gz::toBinString(addressBus) + "[" + gz::toHexString(addressBus, 4) + "]-"
|
||
|
|
+ gz::toBinString(dataBus) + "[" + gz::toHexString(dataBus, 2) + "]";
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
uint32_t byteToMask(char byte, const std::array<uint8_t, 8>& pins) {
|
||
|
|
uint32_t mask = 0;
|
||
|
|
for (int i = 0; i < 8; i++) {
|
||
|
|
if ((1 << i) & byte) { // if ith bit is set, set bit of corresponding pin
|
||
|
|
mask |= (1 << pins.at(i));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return mask;
|
||
|
|
}
|
||
|
|
|
||
|
|
void initPins() {
|
||
|
|
for (int i = 0; i < addressPins.size(); i++) {
|
||
|
|
bcm2835_gpio_fsel(addressPins.at(i), BCM2835_GPIO_FSEL_INPT);
|
||
|
|
}
|
||
|
|
for (int i = 0; i < controlPins.size(); i++) {
|
||
|
|
bcm2835_gpio_fsel(controlPins.at(i), BCM2835_GPIO_FSEL_INPT);
|
||
|
|
}
|
||
|
|
for (int i = 0; i < dataPins.size(); i++) {
|
||
|
|
bcm2835_gpio_fsel(dataPins.at(i), BCM2835_GPIO_FSEL_INPT);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void setIODirection(uint8_t direction) {
|
||
|
|
for (int i = 0; i < dataPins.size(); i++) {
|
||
|
|
bcm2835_gpio_fsel(dataPins.at(i), direction);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
bool isChipEnabled() {
|
||
|
|
// assumes the EEPROM is only hooked up via CE. If CE is low, it will ouput data
|
||
|
|
if (bcm2835_gpio_lev(CEb) == LOW and bcm2835_gpio_lev(RWb) == HIGH) return true;
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
inline bool isRead() {
|
||
|
|
return bcm2835_gpio_lev(CEb);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
uint16_t readAddress() {
|
||
|
|
uint16_t address = 0;
|
||
|
|
for (int i = 0; i < addressPins.size(); i++) {
|
||
|
|
address |= (bcm2835_gpio_lev(addressPins.at(i)) << i);
|
||
|
|
}
|
||
|
|
return address;
|
||
|
|
}
|
||
|
|
|
||
|
|
uint8_t readData() {
|
||
|
|
uint8_t address = 0;
|
||
|
|
for (int i = 0; i < dataPins.size(); i++) {
|
||
|
|
address |= (bcm2835_gpio_lev(dataPins.at(i)) << i);
|
||
|
|
}
|
||
|
|
return address;
|
||
|
|
}
|
||
|
|
|
||
|
|
constexpr std::array<const char*, 256> asciiChars {
|
||
|
|
"␀", "␁", "␂", "␃", "␄", "␅", "␆", "␇", "␈", "␉", "␊", "␋", "␌", "␍", "␎", "␏", "␐", "␑", "␒", "␓", "␔", "␕", "␖", "␗", "␘", "␙", "␚", "␛", "␜", "␝", "␞", "␟", "␠", "!", "\"", "#", "$", "%", "&", "'", "(", ")", "*", "+", ",", "-", ".", "/", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", ":", ";", "<", "=", ">", "?", "@", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "[", "\"", "]", "^", "_", "`", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "{", "|", "}", "~", "␡"
|
||
|
|
};
|
||
|
|
inline void printData(const char& data) {
|
||
|
|
std::cout << '\'' << data << asciiChars.at(data) << "' "<< opCodes.at(data).getName();
|
||
|
|
}
|
||
|
|
|
||
|
|
inline void waitForFallingEdge(uint8_t pin) {
|
||
|
|
while (bcm2835_gpio_lev(pin) == LOW);
|
||
|
|
while (bcm2835_gpio_lev(pin) == HIGH);
|
||
|
|
}
|
||
|
|
inline void waitForRisingEdge(uint8_t pin) {
|
||
|
|
while (bcm2835_gpio_lev(pin) == HIGH);
|
||
|
|
while (bcm2835_gpio_lev(pin) == LOW);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void simulate(std::array<char, UINT16_MAX> data) {
|
||
|
|
initPins();
|
||
|
|
printf("Initalized Pins\n");
|
||
|
|
|
||
|
|
uint16_t lastAddress = 0;
|
||
|
|
bool outputActive = false;
|
||
|
|
|
||
|
|
while (true) {
|
||
|
|
uint16_t currentAddress = readAddress();
|
||
|
|
bool readEnabled = isChipEnabled();
|
||
|
|
if (readEnabled && (!outputActive || (currentAddress != lastAddress))) {
|
||
|
|
setIODirection(BCM2835_GPIO_FSEL_OUTP);
|
||
|
|
outputActive = true;
|
||
|
|
|
||
|
|
uint32_t valueMask = byteToMask(data.at(currentAddress), dataPins);
|
||
|
|
bcm2835_gpio_write_mask(valueMask, ioMask);
|
||
|
|
std::cout << "> Address: " << gz::toBinString(currentAddress) << "[" << gz::toHexString(currentAddress) << "] - " << gz::toBinString(data.at(currentAddress)) << "[" << gz::toHexString(static_cast<uint16_t>(data.at(currentAddress)), 2) << "]";
|
||
|
|
printData(data.at(currentAddress));
|
||
|
|
std::cout << std::endl;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!readEnabled && outputActive) {
|
||
|
|
setIODirection(BCM2835_GPIO_FSEL_INPT);
|
||
|
|
outputActive = false;
|
||
|
|
std::cout << "X Address: " << gz::toBinString(currentAddress) << "[" << gz::toHexString(currentAddress) << "]\n"; //" - " << gz::toBinString(data.at(address)) << std::endl;
|
||
|
|
}
|
||
|
|
|
||
|
|
lastAddress = currentAddress;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void simulateEEPROM(std::stop_token token, const std::array<char, UINT16_MAX>& data) {
|
||
|
|
printf("Begin EEPROM simulation\n");
|
||
|
|
initPins();
|
||
|
|
|
||
|
|
while(!token.stop_requested()) {
|
||
|
|
waitForFallingEdge(CEb);
|
||
|
|
uint16_t currentAddress = readAddress();
|
||
|
|
uint32_t valueMask = byteToMask(data.at(currentAddress), dataPins);
|
||
|
|
setIODirection(BCM2835_GPIO_FSEL_OUTP);
|
||
|
|
bcm2835_gpio_write_mask(valueMask, ioMask);
|
||
|
|
std::cout << "> Address: " << gz::toBinString(currentAddress) << "[" << gz::toHexString(currentAddress) << "] - " << gz::toBinString(data.at(currentAddress)) << "[" << gz::toHexString(static_cast<uint16_t>(data.at(currentAddress)), 2) << "]";
|
||
|
|
waitForRisingEdge(CEb);
|
||
|
|
setIODirection(BCM2835_GPIO_FSEL_INPT);
|
||
|
|
}
|
||
|
|
printf("Exit EEPROM simulation\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void printBusWithClock(std::stop_token token, uint8_t clockPin, const std::atomic<CurrentState>& currentState) {
|
||
|
|
printf("Begin bus printing\n");
|
||
|
|
auto state = currentState.load();
|
||
|
|
while (!token.stop_requested()) {
|
||
|
|
waitForFallingEdge(clockPin);
|
||
|
|
state.RWb = isRead();
|
||
|
|
state.addressBus = readAddress();
|
||
|
|
state.dataBus = readData();
|
||
|
|
std::cout << state.toString() << std::endl;
|
||
|
|
}
|
||
|
|
printf("End bus printing\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void readFile(const char* filepath, std::array<char, UINT16_MAX>& bytes) {
|
||
|
|
std::ifstream file(filepath, std::ios_base::binary | std::ios_base::ate);
|
||
|
|
if (!file.is_open()) {
|
||
|
|
throw std::runtime_error("Error: Could not open file");
|
||
|
|
}
|
||
|
|
auto size = file.tellg();
|
||
|
|
if (size > UINT16_MAX) {
|
||
|
|
throw std::runtime_error("File is larger than UINT16_MAX");
|
||
|
|
}
|
||
|
|
file.seekg (0, std::ios::beg);
|
||
|
|
file.read(bytes.data(), size);
|
||
|
|
file.close();
|
||
|
|
}
|
||
|
|
|
||
|
|
void signalHandler(int signal) {
|
||
|
|
setIODirection(BCM2835_GPIO_FSEL_INPT);
|
||
|
|
bcm2835_close();
|
||
|
|
printf("Caught signal %d, exiting.\n", signal);
|
||
|
|
exit(0);
|
||
|
|
}
|
||
|
|
|
||
|
|
int main(int argc, const char** argv) {
|
||
|
|
if (bcm2835_init() != 1) {
|
||
|
|
printf("Error: Could not initalise gpio libraray\n");
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (argc != 2) {
|
||
|
|
printf("Error: Expected exactly one argument (filename), got %d\n", argc);
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
std::cout << "IOMask=" << gz::toBinString(ioMask) << ", AddressMask=" << gz::toBinString(addressMask) << std::endl;
|
||
|
|
|
||
|
|
std::array<char, UINT16_MAX> bytes{};
|
||
|
|
readFile(argv[1], bytes);
|
||
|
|
|
||
|
|
/* for (int i = 0; i < bytes.size(); i++) { */
|
||
|
|
/* std::cout << gz::toHexString(static_cast<uint8_t>(bytes.at(i))) << " "; */
|
||
|
|
/* if ((i+1) % 8 == 0) { std::cout << " "; } */
|
||
|
|
/* if ((i+1) % 32 == 0) { std::cout << "\n"; } */
|
||
|
|
/* } */
|
||
|
|
/* std::cout << std::endl; */
|
||
|
|
std::cout << "Reset Vector " << gz::toBinString(bytes.at(0x7ffc)) << " - " << gz::toBinString(0x77fd) << std::endl;
|
||
|
|
/* simulate(bytes); */
|
||
|
|
std::jthread eepromT(simulateEEPROM, std::ref(bytes));
|
||
|
|
std::atomic<CurrentState> cs;
|
||
|
|
std::jthread clockT(printBusWithClock, PHI2, std::ref(cs));
|
||
|
|
|
||
|
|
signal(SIGINT, signalHandler);
|
||
|
|
|
||
|
|
while(true);
|
||
|
|
}
|
||
|
|
|