mirror of
https://github.com/TomNisbet/TommyPROM.git
synced 2024-10-07 09:55:52 +00:00
Add 74LS595 code to the HardwareVerify sketch
This commit is contained in:
parent
e45f1e3377
commit
6d9a958907
@ -1,9 +1,28 @@
|
||||
// This controls the shift register that generates the address lines for A0..A15 for most
|
||||
// chip families.
|
||||
//
|
||||
// Note that this uses direct port control instead of digitalWrite calls so that the code
|
||||
// can run fast enough to meet the tBLC requirements for SDP and block writes. This
|
||||
// sacrifices portability and readability for speed.
|
||||
//
|
||||
// This code will only work on Arduino Uno and Nano hardware. The ports for other
|
||||
// Arduinos map to different IO pins.
|
||||
|
||||
#include "PromAddressDriver.h"
|
||||
|
||||
#define ADDR_CLK_HI A3
|
||||
#define ADDR_CLK_LO A4
|
||||
#define ADDR_DATA A5
|
||||
|
||||
// Define masks for the address clk and data lines on PC3..PC5 for direct port control.
|
||||
#define ADDR_CLK_HI_MASK 0x08
|
||||
#define ADDR_CLK_LO_MASK 0x10
|
||||
#define ADDR_DATA_MASK 0x20
|
||||
|
||||
// When using the 74LS595 shift registers, the RCLK lines of both shift registers can be
|
||||
// connected to D13 (PB5).
|
||||
#define RCLK_595_MASK 0x20
|
||||
|
||||
|
||||
void PromAddressDriver::begin()
|
||||
{
|
||||
@ -14,7 +33,7 @@ void PromAddressDriver::begin()
|
||||
digitalWrite(ADDR_DATA, LOW);
|
||||
digitalWrite(ADDR_CLK_LO, LOW);
|
||||
digitalWrite(ADDR_CLK_HI, LOW);
|
||||
|
||||
DDRB |= RCLK_595_MASK; // Set D13 as output
|
||||
|
||||
// To save time, the setAddress only writes the hi byte if it has changed.
|
||||
// The value used to detect the change is initialized to a non-zero value,
|
||||
@ -33,50 +52,22 @@ void PromAddressDriver::setAddress(word address)
|
||||
|
||||
if (hi != lastHi)
|
||||
{
|
||||
setAddressRegisterDirect(ADDR_CLK_HI, hi);
|
||||
setAddressRegister(ADDR_CLK_HI, hi);
|
||||
lastHi = hi;
|
||||
}
|
||||
setAddressRegisterDirect(ADDR_CLK_LO, lo);
|
||||
setAddressRegister(ADDR_CLK_LO, lo);
|
||||
}
|
||||
|
||||
|
||||
// Shift an 8-bit value into one of the address shift registers. Note that
|
||||
// the data pins are tied together, selecting the high or low address register
|
||||
// is a matter of using the correct clock pin to shift the data in.
|
||||
void PromAddressDriver::setAddressRegister(uint8_t clkPin, byte addr)
|
||||
{
|
||||
// Make sure the clock is low to start.
|
||||
digitalWrite(clkPin, LOW);
|
||||
|
||||
// Shift 8 bits in, starting with the MSB.
|
||||
for (int ix = 0; (ix < 8); ix++)
|
||||
{
|
||||
// Set the data bit
|
||||
if (addr & 0x80)
|
||||
{
|
||||
digitalWrite(ADDR_DATA, HIGH);
|
||||
}
|
||||
else
|
||||
{
|
||||
digitalWrite(ADDR_DATA, LOW);
|
||||
}
|
||||
|
||||
digitalWrite(clkPin, HIGH); // Clock in a bit
|
||||
digitalWrite(clkPin, LOW); // Reset the clock pin
|
||||
addr <<= 1;
|
||||
}
|
||||
}
|
||||
|
||||
// Shift an 8-bit value into one of the address shift registers. Note that
|
||||
// the data pins are tied together, selecting the high or low address register
|
||||
// is a matter of using the correct clock pin to shift the data in.
|
||||
void PromAddressDriver::setAddressRegisterDirect(uint8_t clkPin, byte addr)
|
||||
{
|
||||
byte mask = 0;
|
||||
if (clkPin == A3)
|
||||
mask = 0x08;
|
||||
else if (clkPin == A4)
|
||||
mask = 0x10;
|
||||
if (clkPin == ADDR_CLK_HI)
|
||||
mask = ADDR_CLK_HI_MASK;
|
||||
else if (clkPin == ADDR_CLK_LO)
|
||||
mask = ADDR_CLK_LO_MASK;
|
||||
|
||||
// Make sure the clock is low to start.
|
||||
PORTC &= ~mask;
|
||||
@ -87,11 +78,11 @@ void PromAddressDriver::setAddressRegisterDirect(uint8_t clkPin, byte addr)
|
||||
// Set the data bit
|
||||
if (addr & 0x80)
|
||||
{
|
||||
PORTC |= 0x20;
|
||||
PORTC |= ADDR_DATA_MASK;
|
||||
}
|
||||
else
|
||||
{
|
||||
PORTC &= 0xdf;
|
||||
PORTC &= ~ADDR_DATA_MASK;
|
||||
}
|
||||
|
||||
// Toggle the clock high then low
|
||||
@ -100,5 +91,12 @@ void PromAddressDriver::setAddressRegisterDirect(uint8_t clkPin, byte addr)
|
||||
PORTC &= ~mask;
|
||||
addr <<= 1;
|
||||
}
|
||||
}
|
||||
|
||||
// Toggle the output latch for 74LS595 hardware. For the default TommyPROM hardware
|
||||
// this just harmlessly writes to the D13 line that isn't connected to anything.
|
||||
PORTB &= ~RCLK_595_MASK;
|
||||
delayMicroseconds(1);
|
||||
PORTB |= RCLK_595_MASK;
|
||||
delayMicroseconds(1);
|
||||
PORTB &= ~RCLK_595_MASK;
|
||||
}
|
||||
|
@ -10,9 +10,7 @@ class PromAddressDriver {
|
||||
|
||||
private:
|
||||
static void setAddressRegister(uint8_t clkPin, byte addr);
|
||||
static void setAddressRegisterDirect(uint8_t clkPin, byte addr);
|
||||
};
|
||||
|
||||
|
||||
#endif // #define INCLUDE_PROM_ADDRESS_DRIVER_H
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user