Revert "ADC: only read channels that are actually being used"

This reverts commit 95e6bb26f4772ca8c7faa62215de6f078d3df3c7.

ADC will be disabled on APM2
This commit is contained in:
Andrew Tridgell 2011-12-17 07:21:43 +11:00
parent c18ad75504
commit 3654c714e9
1 changed files with 2 additions and 33 deletions

View File

@ -63,11 +63,6 @@ static volatile uint32_t _sum[8];
// how many values we've accumulated since last read
static volatile uint16_t _count[8];
// a mask of what channels are actually being read. If a channel has
// never been read, then don't bother gathering it. That saves us a
// lot of cycles in the timer call
static uint8_t enable_mask;
static uint32_t last_ch6_micros;
// TCNT2 values for various interrupt rates,
@ -92,35 +87,15 @@ static inline unsigned char ADC_SPI_transfer(unsigned char data)
void AP_ADC_ADS7844::read(void)
{
uint8_t ch;
unsigned char enable_cmd[9];
uint8_t num_enabled = 0;
if (enable_mask == 0) {
// no channels to read
return;
}
for (ch = 0; ch < 8; ch++) {
if (enable_mask & (1<<ch)) {
enable_cmd[num_enabled++] = adc_cmd[ch];
}
}
enable_cmd[num_enabled] = 0;
num_enabled = 0;
bit_clear(PORTC, 4); // Enable Chip Select (PIN PC4)
ADC_SPI_transfer(enable_cmd[0]); // Command to read the first channel
ADC_SPI_transfer(adc_cmd[0]); // Command to read the first channel
for (ch = 0; ch < 8; ch++) {
uint16_t v;
if ((enable_mask & (1<<ch)) == 0) {
continue;
}
v = ADC_SPI_transfer(0) << 8; // Read first byte
v |= ADC_SPI_transfer(enable_cmd[++num_enabled]); // Read second byte and send next command
v |= ADC_SPI_transfer(adc_cmd[ch + 1]); // Read second byte and send next command
if (v & 0x8007) {
// this is a 12-bit ADC, shifted by 3 bits.
@ -193,8 +168,6 @@ float AP_ADC_ADS7844::Ch(uint8_t ch_num)
uint16_t count;
uint32_t sum;
enable_mask |= (1<<ch_num);
// ensure we have at least one value
while (_count[ch_num] == 0) /* noop */ ;
@ -220,10 +193,6 @@ uint32_t AP_ADC_ADS7844::Ch6(const uint8_t *channel_numbers, uint16_t *result)
uint32_t sum[6];
uint8_t i;
for (i=0; i<6; i++) {
enable_mask |= (1<<channel_numbers[i]);
}
// ensure we have at least one value
for (i=0; i<6; i++) {
while (_count[channel_numbers[i]] == 0) /* noop */;