From ac8ca3601af2e3d243339614e11d5f7f81d2f6b6 Mon Sep 17 00:00:00 2001
From: Paul Schroeder <milkpirate@users.noreply.github.com>
Date: Tue, 14 Jan 2025 21:36:30 +0100
Subject: [PATCH 1/5] feat(src/machine/nrf52xxx/adc): move init to init
function
Signed-off-by: Paul Schroeder <milkpirate@users.noreply.github.com>
---
src/machine/machine_nrf52xxx.go | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/src/machine/machine_nrf52xxx.go b/src/machine/machine_nrf52xxx.go
index ee035b74d6..e514756a06 100644
--- a/src/machine/machine_nrf52xxx.go
+++ b/src/machine/machine_nrf52xxx.go
@@ -14,19 +14,17 @@ func CPUFrequency() uint32 {
// InitADC initializes the registers needed for ADC.
func InitADC() {
- return // no specific setup on nrf52 machine.
-}
-
-// Configure configures an ADC pin to be able to read analog data.
-func (a ADC) Configure(config ADCConfig) {
// Enable ADC.
- // The ADC does not consume a noticeable amount of current simply by being
- // enabled.
+ // The ADC does not consume a noticeable amount of current by being enabled.
nrf.SAADC.ENABLE.Set(nrf.SAADC_ENABLE_ENABLE_Enabled << nrf.SAADC_ENABLE_ENABLE_Pos)
+}
- // Use fixed resolution of 12 bits.
- // TODO: is it useful for users to change this?
- nrf.SAADC.RESOLUTION.Set(nrf.SAADC_RESOLUTION_VAL_12bit)
+// Configure configures an ADC pin to be able to read analog data.
+// Reference voltage can be 150, 300, 600, 1200, 1800, 2400, 3000(default), 3600 mV
+// Resolution can be 8, 10, 12(default), 14 bits
+// SampleTime will be ceiled to 3(default), 5, 10, 15, 20 or 40(max) µS respectively
+// Samples can be 1(default), 2, 4, 8, 16, 32, 64, 128, 256 samples
+func (a *ADC) Configure(config ADCConfig) {
var configVal uint32 = nrf.SAADC_CH_CONFIG_RESP_Bypass<<nrf.SAADC_CH_CONFIG_RESP_Pos |
nrf.SAADC_CH_CONFIG_RESP_Bypass<<nrf.SAADC_CH_CONFIG_RESN_Pos |
From 10e61240d88ab8a069aecbf9d0279b5624dae0a0 Mon Sep 17 00:00:00 2001
From: Paul Schroeder <milkpirate@users.noreply.github.com>
Date: Tue, 14 Jan 2025 21:37:41 +0100
Subject: [PATCH 2/5] chore(src/machine/nrf52xxx/adc): fix typo and formatting
Signed-off-by: Paul Schroeder <milkpirate@users.noreply.github.com>
---
src/machine/machine_nrf52xxx.go | 14 +++-----------
1 file changed, 3 insertions(+), 11 deletions(-)
diff --git a/src/machine/machine_nrf52xxx.go b/src/machine/machine_nrf52xxx.go
index e514756a06..9cd59d839b 100644
--- a/src/machine/machine_nrf52xxx.go
+++ b/src/machine/machine_nrf52xxx.go
@@ -49,7 +49,7 @@ func (a *ADC) Configure(config ADCConfig) {
case 3600: // 3.6V
configVal |= nrf.SAADC_CH_CONFIG_GAIN_Gain1_6 << nrf.SAADC_CH_CONFIG_GAIN_Pos
default:
- // TODO: return an error
+ // TODO: return an error, will that interfere with any interfaced if one will be?
}
// Source resistance, according to table 89 on page 364 of the nrf52832 datasheet.
@@ -100,36 +100,28 @@ func (a *ADC) Configure(config ADCConfig) {
nrf.SAADC.CH[0].CONFIG.Set(configVal)
}
-// Get returns the current value of a ADC pin in the range 0..0xffff.
func (a ADC) Get() uint16 {
+// Get returns the current value of an ADC pin in the range 0..0xffff.
var pwmPin uint32
var rawValue volatile.Register16
switch a.Pin {
case 2:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput0
-
case 3:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput1
-
case 4:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput2
-
case 5:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput3
-
case 28:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput4
-
case 29:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput5
-
case 30:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput6
-
case 31:
pwmPin = nrf.SAADC_CH_PSELP_PSELP_AnalogInput7
-
default:
return 0
}
@@ -194,7 +186,7 @@ type SPIConfig struct {
Mode uint8
}
-// Configure is intended to setup the SPI interface.
+// Configure is intended to set up the SPI interface.
func (spi SPI) Configure(config SPIConfig) error {
// Disable bus to configure it
spi.Bus.ENABLE.Set(nrf.SPIM_ENABLE_ENABLE_Disabled)
From bfa1551f4afc0bc72cac530390333d0861271d0d Mon Sep 17 00:00:00 2001
From: Paul Schroeder <milkpirate@users.noreply.github.com>
Date: Tue, 14 Jan 2025 21:39:16 +0100
Subject: [PATCH 3/5] feat(src/machine/nrf52xxx/adc): make resolution
configurable
Signed-off-by: Paul Schroeder <milkpirate@users.noreply.github.com>
---
src/machine/machine_nrf52xxx.go | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/src/machine/machine_nrf52xxx.go b/src/machine/machine_nrf52xxx.go
index 9cd59d839b..2cb6615bb9 100644
--- a/src/machine/machine_nrf52xxx.go
+++ b/src/machine/machine_nrf52xxx.go
@@ -52,8 +52,23 @@ func (a *ADC) Configure(config ADCConfig) {
// TODO: return an error, will that interfere with any interfaced if one will be?
}
- // Source resistance, according to table 89 on page 364 of the nrf52832 datasheet.
- // https://infocenter.nordicsemi.com/pdf/nRF52832_PS_v1.4.pdf
+ var resolution uint32
+ switch config.Resolution {
+ case 8:
+ resolution = nrf.SAADC_RESOLUTION_VAL_8bit
+ case 10:
+ resolution = nrf.SAADC_RESOLUTION_VAL_10bit
+ case 12:
+ resolution = nrf.SAADC_RESOLUTION_VAL_12bit
+ case 14:
+ resolution = nrf.SAADC_RESOLUTION_VAL_14bit
+ default:
+ resolution = nrf.SAADC_RESOLUTION_VAL_12bit
+ }
+ nrf.SAADC.RESOLUTION.Set(resolution)
+
+ // Source resistance, according to table 41 on page 676 of the nrf52832 datasheet.
+ // https://docs-be.nordicsemi.com/bundle/ps_nrf52840/attach/nRF52840_PS_v1.11.pdf?_LANG=enus
if config.SampleTime <= 3 { // <= 10kΩ
configVal |= nrf.SAADC_CH_CONFIG_TACQ_3us << nrf.SAADC_CH_CONFIG_TACQ_Pos
} else if config.SampleTime <= 5 { // <= 40kΩ
@@ -100,8 +115,8 @@ func (a *ADC) Configure(config ADCConfig) {
nrf.SAADC.CH[0].CONFIG.Set(configVal)
}
-func (a ADC) Get() uint16 {
// Get returns the current value of an ADC pin in the range 0..0xffff.
+func (a *ADC) Get() uint16 {
var pwmPin uint32
var rawValue volatile.Register16
From de4ef7a3e2fe3658a4d3743340fe8c178a6164dd Mon Sep 17 00:00:00 2001
From: Paul Schroeder <milkpirate@users.noreply.github.com>
Date: Tue, 14 Jan 2025 21:52:50 +0100
Subject: [PATCH 4/5] fix(src/machine/nrf52xxx/adc): Register16.Get() already
returns uint16, bit shifting does not make sense, <0 check neither
Signed-off-by: Paul Schroeder <milkpirate@users.noreply.github.com>
---
src/machine/machine_nrf52xxx.go | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/src/machine/machine_nrf52xxx.go b/src/machine/machine_nrf52xxx.go
index 2cb6615bb9..16c4040248 100644
--- a/src/machine/machine_nrf52xxx.go
+++ b/src/machine/machine_nrf52xxx.go
@@ -169,13 +169,7 @@ func (a *ADC) Get() uint16 {
}
nrf.SAADC.EVENTS_STOPPED.Set(0)
- value := int16(rawValue.Get())
- if value < 0 {
- value = 0
- }
-
- // Return 16-bit result from 12-bit value.
- return uint16(value << 4)
+ return rawValue.Get()
}
// SPI on the NRF.
From 33e7cd033711e727678ceed776ef1f1a1e5cf330 Mon Sep 17 00:00:00 2001
From: Paul Schroeder <milkpirate@users.noreply.github.com>
Date: Sat, 18 Jan 2025 17:07:12 +0100
Subject: [PATCH 5/5] chore(review): honor
Signed-off-by: Paul Schroeder <milkpirate@users.noreply.github.com>
---
src/machine/machine_nrf52xxx.go | 18 ++++++++++++++++--
1 file changed, 16 insertions(+), 2 deletions(-)
diff --git a/src/machine/machine_nrf52xxx.go b/src/machine/machine_nrf52xxx.go
index 16c4040248..2d3545b7a9 100644
--- a/src/machine/machine_nrf52xxx.go
+++ b/src/machine/machine_nrf52xxx.go
@@ -25,7 +25,6 @@ func InitADC() {
// SampleTime will be ceiled to 3(default), 5, 10, 15, 20 or 40(max) µS respectively
// Samples can be 1(default), 2, 4, 8, 16, 32, 64, 128, 256 samples
func (a *ADC) Configure(config ADCConfig) {
-
var configVal uint32 = nrf.SAADC_CH_CONFIG_RESP_Bypass<<nrf.SAADC_CH_CONFIG_RESP_Pos |
nrf.SAADC_CH_CONFIG_RESP_Bypass<<nrf.SAADC_CH_CONFIG_RESN_Pos |
nrf.SAADC_CH_CONFIG_REFSEL_Internal<<nrf.SAADC_CH_CONFIG_REFSEL_Pos |
@@ -169,7 +168,22 @@ func (a *ADC) Get() uint16 {
}
nrf.SAADC.EVENTS_STOPPED.Set(0)
- return rawValue.Get()
+ // convert to 16 bit resolution/value
+ var resolutionAdjustment uint8
+ switch nrf.SAADC.RESOLUTION.Get() {
+ case nrf.SAADC_RESOLUTION_VAL_8bit:
+ resolutionAdjustment = 8
+ case nrf.SAADC_RESOLUTION_VAL_10bit:
+ resolutionAdjustment = 6
+ case nrf.SAADC_RESOLUTION_VAL_12bit:
+ resolutionAdjustment = 4
+ case nrf.SAADC_RESOLUTION_VAL_14bit:
+ resolutionAdjustment = 2
+ default:
+ resolutionAdjustment = 4 // 12bit
+ }
+
+ return rawValue.Get() << resolutionAdjustment
}
// SPI on the NRF.