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Small optimization to address calculation

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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 PORTA = u.addrBytes[0]; // A0-A7
PORTC = u.addrBytes[1]; // A8-A15 PORTC = u.addrBytes[1]; // A8-A15
// A16-A20 are special because they are split up...(We use PORTD pins 0, 1, 4, 5, 6) // 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]; PORTD = u.addrBytes[2];
} }
@ -477,7 +477,7 @@ void ParallelBus_WriteCycle(uint32_t address, uint32_t data)
u.word = address; u.word = address;
PORTA = u.bytes[0]; PORTA = u.bytes[0];
PORTC = u.bytes[1]; 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]; PORTD = u.bytes[2];
// If the data port is not already set as outputs, set it to be outputs now // 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; u.word = address;
PORTA = u.bytes[0]; PORTA = u.bytes[0];
PORTC = u.bytes[1]; 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]; PORTD = u.bytes[2];
// Start the SPI read. Each clock cycle at 16 MHz is 62.5 nanoseconds. We don't want to // 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++; u.word = startAddress++;
PORTA = u.bytes[0]; PORTA = u.bytes[0];
PORTC = u.bytes[1]; 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]; PORTD = u.bytes[2];
// Start the SPI read. Each clock cycle at 16 MHz is 62.5 nanoseconds. We don't want to // Start the SPI read. Each clock cycle at 16 MHz is 62.5 nanoseconds. We don't want to