varpa: initial public commit

1 files changed, 129 insertions, 0 deletions

diff --git a/firmware/src/driver/mcp3202.c b/firmware/src/driver/mcp3202.c
new file mode 100644
index 0000000..07f84db
--- /dev/null
+++ b/firmware/src/driver/mcp3202.c
@@ -0,0 +1,129 @@
+/**
+ * 
+ * Author: Dylan Muller
+ * Copyright (c) 2025 
+ * All rights reserved.
+ * 
+ * - Commercial/IP use prohibited.
+ * - Attribution required.
+ * See License.txt
+ *
+ */
+
+#include "setup.h"
+
+#include "peripheral/spi.h"
+#include "driver/mcp3202.h"
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+
+void adc_init(void)
+{
+    MCP3202_DEV_0_DDR |= (1 << MCP3202_DEV_0_SS);
+    MCP3202_DEV_1_DDR |= (1 << MCP3202_DEV_1_SS);
+
+    MCP3202_DEV_0_PORT &= ~(1 << MCP3202_DEV_0_SS);
+    MCP3202_DEV_1_PORT &= ~(1 << MCP3202_DEV_1_SS);
+
+    _delay_ms(TRANSACT_DELAY_MS);
+
+    MCP3202_DEV_0_PORT |= (1 << MCP3202_DEV_0_SS);
+    MCP3202_DEV_1_PORT |= (1 << MCP3202_DEV_1_SS);
+
+    _delay_ms(TRANSACT_DELAY_MS);
+}
+
+uint16_t adc_read(
+    uint8_t id,
+    uint8_t conv_bypass
+)
+{
+    uint8_t dev_id = 0x0;
+    uint8_t dev_ch = 0x0;
+    uint8_t dev_ss = 0x0;
+    uint8_t* dev_port = 0x0;
+    uint8_t cmd_buf[3] = {0x0, 0x0, 0x0};
+    uint16_t adc_daq = 0x0;
+
+    switch(id)
+    {
+        case MCP3202_ID_FW_POWER:
+            dev_id = MCP3202_DEV_FW_POWER;
+            dev_ch = MCP3202_CHN_FW_POWER;
+            break;
+        
+        case MCP3202_ID_REV_POWER:
+            dev_id = MCP3202_DEV_REV_POWER;
+            dev_ch = MCP3202_CHN_REV_POWER;
+            break;
+
+        case MCP3202_ID_DRAIN_VOLT:
+            dev_id = MCP3202_DEV_DRAIN_VOLT;
+            dev_ch = MCP3202_CHN_DRAIN_VOLT;
+            break;
+
+        case MCP3202_ID_DRAIN_AMP:
+            dev_id = MCP3202_DEV_DRAIN_AMP;
+            dev_ch = MCP3202_CHN_DRAIN_AMP;
+            break;
+    }
+
+    switch(dev_id)
+    {
+        case MCP3202_DEV_0:
+            dev_port = (uint8_t*)&MCP3202_DEV_0_PORT;
+            dev_ss = MCP3202_DEV_0_SS;
+            break;
+        
+        case MCP3202_DEV_1:
+            dev_port = (uint8_t*)&MCP3202_DEV_1_PORT;
+            dev_ss = MCP3202_DEV_1_SS;
+            break;
+    }
+
+    cmd_buf[0] = MCP3202_REQ_START;
+    cmd_buf[1] = (dev_ch == MCP3202_CHN_0) ? MCP3202_REQ_CH0 : MCP3202_REQ_CH1;
+    cmd_buf[2] = MCP3202_REQ_PAD;
+
+    spi_start(cmd_buf, cmd_buf, sizeof(cmd_buf), dev_port, dev_ss);
+    spi_flush();
+
+    adc_daq = (uint16_t)(cmd_buf[MCP3202_DAQ_MSB]);
+    adc_daq |= ((uint16_t)(cmd_buf[MCP3202_DAQ_LSB] & 0xF) << 8);
+    adc_daq = adc_daq & 0xFFF;
+
+    if (conv_bypass == 0)
+    {
+        switch(id)
+        {
+            case MCP3202_ID_DRAIN_VOLT:
+                adc_daq = (uint32_t)(((uint32_t)adc_daq * MCP3202_DRAIN_VOLT_GAIN)/10);
+                break;
+            case MCP3202_ID_DRAIN_AMP:
+                adc_daq = (uint32_t)(((uint32_t)adc_daq * 10)/MCP3202_DRAIN_AMP_GAIN);
+                break;
+        }
+    }
+        
+    return (uint16_t)adc_daq;
+}
+
+uint16_t adc_read_n(
+    uint8_t id,
+    uint8_t n
+)
+{
+    uint32_t x = 0;
+    uint8_t i = 0;
+
+    for (i = 0; i < n; i++)
+    {
+        x += adc_read(id, 0);
+    }
+
+    x /= n;
+
+    return (uint16_t)x;
+}