From b6e421bcbede4750ed59bc7a87a36b0b9370a685 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?K=C3=A9vin=20Redon?= Date: Thu, 26 Mar 2020 01:47:12 +0100 Subject: card_emu: use edge-triggered VCC ADC logic Before this patch, we used to st ci->vcc_active depending on the instantaneous ADC reading of VCC. Is it > .5v, we claim VCC is active, and if it's below, VCC is inactive. With this patch we move to an edge triggered approach: Only change ci->vcc_active if the previous reading was different from the current reading. FIXME: why? Change-Id: I71b703162219484e43638f1f2f692e9dd554ef55 --- firmware/libcommon/source/mode_cardemu.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/firmware/libcommon/source/mode_cardemu.c b/firmware/libcommon/source/mode_cardemu.c index 127556c..2930e73 100644 --- a/firmware/libcommon/source/mode_cardemu.c +++ b/firmware/libcommon/source/mode_cardemu.c @@ -70,6 +70,7 @@ struct cardem_inst { const Pin pin_insert; #ifdef DETECT_VCC_BY_ADC uint32_t vcc_uv; + uint32_t vcc_uv_last; #endif bool vcc_active; bool vcc_active_last; @@ -233,6 +234,7 @@ static uint16_t compute_next_timeout(struct cardem_inst *ci) * \param[in] inst_num Instance number, range 0..1 (some boards only '0' permitted) */ static void usart_irq_rx(uint8_t inst_num) { + OSMO_ASSERT(inst_num < ARRAY_SIZE(cardem_inst)); Usart *usart = get_usart_by_chan(inst_num); struct cardem_inst *ci = &cardem_inst[inst_num]; uint32_t csr; @@ -441,10 +443,14 @@ static int card_vcc_adc_init(void) static void process_vcc_adc(struct cardem_inst *ci) { - if (ci->vcc_uv >= VCC_UV_THRESH_3V) + if (ci->vcc_uv >= VCC_UV_THRESH_3V && + ci->vcc_uv_last < VCC_UV_THRESH_3V) { ci->vcc_active = true; - else + } else if (ci->vcc_uv < VCC_UV_THRESH_3V && + ci->vcc_uv_last >= VCC_UV_THRESH_3V) { ci->vcc_active = false; + } + ci->vcc_uv_last = ci->vcc_uv; } void ADC_IrqHandler(void) -- cgit v1.2.3