From 1cc4785ddb6db45452c3f0e91ce4e910c98dd5f1 Mon Sep 17 00:00:00 2001
From: Wolfgang Hottgenroth <wolfgang.hottgenroth@icloud.com>
Date: Thu, 21 Mar 2024 20:55:41 +0100
Subject: [PATCH] refactor SPI handling and introduce SPI CS, forgotten files

---
 game-ctrl/disabled/led.c | 55 ++++++++++++++++++++++++++++++++++++++++
 game-ctrl/disabled/led.h | 15 +++++++++++
 game-ctrl/spi.c          | 50 ++++++++++++++++++++++++++++++++++++
 game-ctrl/spi.h          | 16 ++++++++++++
 4 files changed, 136 insertions(+)
 create mode 100644 game-ctrl/disabled/led.c
 create mode 100644 game-ctrl/disabled/led.h
 create mode 100644 game-ctrl/spi.c
 create mode 100644 game-ctrl/spi.h

diff --git a/game-ctrl/disabled/led.c b/game-ctrl/disabled/led.c
new file mode 100644
index 0000000..51ecd31
--- /dev/null
+++ b/game-ctrl/disabled/led.c
@@ -0,0 +1,55 @@
+#include "led.h"
+#include <msp430g2553.h>
+#include "scheduler.h"
+#include <stdlib.h>
+
+
+void ledGreenOn() {
+  P1OUT |= BIT0;
+}
+
+void ledGreenOff() {
+  P1OUT &= ~BIT0;
+}
+
+void ledGreenToggle() {
+  P1OUT ^= BIT0;
+}
+
+void ledBlueOn() {
+  P1OUT |= BIT1;
+}
+
+void ledBlueOff() {
+  P1OUT &= ~BIT1;
+}
+
+void ledBlueToggle() {
+  P1OUT ^= BIT1;
+}
+
+void ledExec(void *args) {
+  static uint16_t i = 0;
+
+  if (i == 0) {
+    ledGreenOff();
+    i = 1;
+  } else {
+    ledGreenOn();
+    i = 0;
+  }
+}
+
+void ledInit() {
+    // BIT0: green
+    // BIT1: blue
+    P1DIR |= BIT0|BIT1;
+
+    ledGreenOff();
+    ledBlueOff();
+
+
+//    schAdd(ledExec, NULL, 0, 500);
+}
+
+
diff --git a/game-ctrl/disabled/led.h b/game-ctrl/disabled/led.h
new file mode 100644
index 0000000..207797e
--- /dev/null
+++ b/game-ctrl/disabled/led.h
@@ -0,0 +1,15 @@
+#ifndef LED_H_
+#define LED_H_
+
+
+void ledBlueOff();
+void ledBlueOn();
+void ledBlueToggle();
+void ledGreenOff();
+void ledGreenOn();
+void ledGreenToggle();
+
+void ledInit();
+void ledExec();
+
+#endif /* LED_H_ */
diff --git a/game-ctrl/spi.c b/game-ctrl/spi.c
new file mode 100644
index 0000000..2e236ab
--- /dev/null
+++ b/game-ctrl/spi.c
@@ -0,0 +1,50 @@
+#include <msp430g2553.h>
+#include "spi.h"
+
+void spiInit() {
+  // SPI in master mode
+  UCB0CTL0 = UCMST;
+  // SPI timing config
+  UCB0CTL1 = UCSSEL_3;
+  // Faster than 8 ends up in strange communication errors
+  // between the both MCUs.
+  // With 8 the transfer of a complete 110 pixel canvas takes
+  // about 720us.
+  // 8 was still too fast and caused problems.
+  UCB0BR0 = 16; 
+  UCB0BR1 = 0;
+
+  // BIT5: UCB0CLK
+  // BIT6: UCB0SOMI
+  // BIT7: UCB0SIMO
+  P1SEL |= BIT5 | BIT6 | BIT7;
+  P1SEL2 |= BIT5 | BIT6 | BIT7;
+  P1DIR |= BIT5 | BIT7;
+
+  // Device Select Lines: 0: Canvas, 1: Display, 2: Sound
+  P1DIR |= BIT0 | BIT1 | BIT2;
+  // Disable all of them
+  P1OUT |= BIT0 | BIT1 | BIT2;
+
+  // enable SPI module
+  UCB0CTL1 &= ~UCSWRST;
+}
+
+void spiSendBegin(t_SpiDeviceSelector d) {
+  uint16_t bit = ((uint16_t[]){ BIT0, BIT1, BIT2 })[d];
+  P1OUT &= ~bit;
+}
+
+void spiSendEnd(t_SpiDeviceSelector d) {
+  while (UCB0STAT & UCBUSY);
+  uint16_t bit = ((uint16_t[]){ BIT0, BIT1, BIT2 })[d];
+  P1OUT |= bit;
+}
+
+void spiSendOctet(uint8_t v) {
+  // wait for TX buffer empty
+  while (!(UC0IFG & UCB0TXIFG));
+  // load octet into TX buffer
+  UCB0TXBUF = v;
+}
+
diff --git a/game-ctrl/spi.h b/game-ctrl/spi.h
new file mode 100644
index 0000000..9a3efaa
--- /dev/null
+++ b/game-ctrl/spi.h
@@ -0,0 +1,16 @@
+#ifndef _SPI_H_
+#define _SPI_H_
+
+#include <stdint.h>
+
+
+typedef enum { e_SPI_CANVAS, e_SPI_DISPLAY, e_SPI_SOUND } t_SpiDeviceSelector;
+
+void spiInit();
+void spiSendBegin(t_SpiDeviceSelector d);
+void spiSendEnd(t_SpiDeviceSelector d);
+void spiSendOctet(uint8_t v); 
+
+
+
+#endif // _SPI_H_