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Diffstat (limited to 'src/peripherals/avrdx-slpctrl.ts')
-rw-r--r--src/peripherals/avrdx-slpctrl.ts35
1 files changed, 35 insertions, 0 deletions
diff --git a/src/peripherals/avrdx-slpctrl.ts b/src/peripherals/avrdx-slpctrl.ts
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+++ b/src/peripherals/avrdx-slpctrl.ts
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+// AVR-Dx SLPCTRL - Sleep Controller
+// Handles the SLEEP instruction by fast-forwarding to the next clock event.
+
+import type { CPU } from 'avr8js/cpu/cpu';
+
+const CTRLA = 0;
+const SEN_bm = 0x01;
+// const SMODE_gm = 0x06;
+
+export class AVRDxSLPCTRL {
+ sleepUntil: number = 0;
+
+ constructor(private cpu: CPU, private base: number) {
+ // CTRLA - sleep mode + sleep enable
+ cpu.writeHooks[base + CTRLA] = (value) => {
+ cpu.data[base + CTRLA] = value;
+ return true;
+ };
+
+ // Hook the SLEEP instruction
+ cpu.onSleep = () => {
+ this.handleSleep();
+ };
+ }
+
+ private handleSleep() {
+ const ctrla = this.cpu.data[this.base + CTRLA];
+ if (!(ctrla & SEN_bm)) return; // sleep not enabled
+
+ const nextEvent = (this.cpu as any).nextClockEvent;
+ if (nextEvent) {
+ this.sleepUntil = Math.min(this.sleepUntil, nextEvent.cycles);
+ }
+ }
+}