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Small optimization to address calculation 

Due to integer promotion, the calculation of what to write to PORTD was
inefficient. Based on my benchmarking, it didn't really matter though.
This commit is contained in:
Doug Brown 2020-11-25 22:36:24 -08:00 committed by Doug Brown
parent 9521494971
commit 4394533d88
1 changed files with 4 additions and 4 deletions
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8
hal/at90usb646/parallel_bus.c
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@ -141,7 +141,7 @@ void ParallelBus_SetAddress(uint32_t address)
PORTA = u.addrBytes[0]; // A0-A7
PORTC = u.addrBytes[1]; // A8-A15
// A16-A20 are special because they are split up...(We use PORTD pins 0, 1, 4, 5, 6)
u.addrBytes[2] = (u.addrBytes[2] & 0x03) | ((u.addrBytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
u.addrBytes[2] = (u.addrBytes[2] & 0x03) | (uint8_t)((u.addrBytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
PORTD = u.addrBytes[2];
}
@ -477,7 +477,7 @@ void ParallelBus_WriteCycle(uint32_t address, uint32_t data)
u.word = address;
PORTA = u.bytes[0];
PORTC = u.bytes[1];
u.bytes[2] = (u.bytes[2] & 0x03) | ((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
u.bytes[2] = (u.bytes[2] & 0x03) | (uint8_t)((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
PORTD = u.bytes[2];
// If the data port is not already set as outputs, set it to be outputs now
@ -566,7 +566,7 @@ uint32_t ParallelBus_ReadCycle(uint32_t address)
u.word = address;
PORTA = u.bytes[0];
PORTC = u.bytes[1];
u.bytes[2] = (u.bytes[2] & 0x03) | ((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
u.bytes[2] = (u.bytes[2] & 0x03) | (uint8_t)((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
PORTD = u.bytes[2];
// Start the SPI read. Each clock cycle at 16 MHz is 62.5 nanoseconds. We don't want to
@ -646,7 +646,7 @@ void ParallelBus_Read(uint32_t startAddress, uint32_t *buf, uint16_t len)
u.word = startAddress++;
PORTA = u.bytes[0];
PORTC = u.bytes[1];
u.bytes[2] = (u.bytes[2] & 0x03) | ((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
u.bytes[2] = (u.bytes[2] & 0x03) | (uint8_t)((u.bytes[2] & 0x1C) << 2) | (PORTD & 0x8C);
PORTD = u.bytes[2];
// Start the SPI read. Each clock cycle at 16 MHz is 62.5 nanoseconds. We don't want to